At a most basic level, patent infringement in the U.S. involves making, using, selling, offering for sale, importing into the USA a patented invention without authorization. Although there are some additional grounds for infringement that may apply in some other circumstances. All grounds for infringement fall into two general categories: direct infringement and indirect infringement. These categories refer to who is being accused and whether they are directly responsible or instead indirectly or partly responsible. There are multiple types of infringement under each category. These include literal or Doctrine of Equivalents infringement, and, for indirect infringement, active inducement of infringement, contributory infringement, and certain activities related to components for export from the USA. Each of these provisions, set forth in § 271 of the U.S. patent laws, is taken up further below.
Direct Infringement
Direct patent infringement means that an accused party is directly responsible for infringement a patent. Direct infringement requires that each and every limitation (or element) of at least one claim of an asserted patent is met either literally or under the Doctrine of Equivalents. If a limitation of a given patent claim is not present in the accused product or process, either literally or equivalently, then that claim is not infringed.
The sorts of things that can constitute direct infringement include the following:
making (that is, manufacturing) the patented invention in the USA (35 U.S.C. § 271(a))
submitting a new drug application for U.S. regulatory approval (Hatch-Waxman Act; 35 U.S.C. § 271(e))
importing into the USA, or offering to sell, selling, or using within the USA, a product which is made outside the USA by a process patented in the USA, unless it is materially changed by subsequent processes or it becomes a trivial and nonessential component of another product (35 U.S.C. § 271(g))
Certain additional rights to exclude specific to plant patents (35 U.S.C. § 163)
There are two ways of finding infringement that differ in terms of how the accused product or process relates to the scope of the claim(s) of the asserted patent:
Literal Infringement
Infringement Under the Doctrine of Equivalents (also called infringement by equivalence)
Literal Infringement
Literal infringement means that the accused product or process falls within the scope of the asserted claim(s) as construed by a court. Under U.S. law, infringement analysis is a two-step process. It involves, first, construing the claims to ascertain their meaning to a person of ordinary skill in the art and to resolve any ambiguities or disputes over that meaning, and, second, comparing the accused product/process to the properly construed claim(s). Literal infringement is present when the accused infringer meets each and every limitation (or element) of an asserted patent claim exactly, as properly construed. Any deviation from a claim limitation (as properly construed) precludes a finding of literal infringement.
Infringement Under the Doctrine of Equivalents
Under the Doctrine of Equivalents, a product or process that does not literally infringe upon the express terms of a patent claim may nonetheless still be found to infringe if there is “equivalence” between the elements of the accused product or process and claimed elements of the patented invention. This type of infringement arises when the accused product or process is outside the literal scope of at least one limitation of an asserted claim, as properly construed. Patentees rely on the Doctrine of Equivalents under the second step of the infringement analysis, if at all, only if literal infringement cannot be established. Otherwise, the Doctrine of Equivalents can apply to the same set of activities as for literal infringement.
This is an equitable doctrine meant to “temper unsparing logic” that “would place the inventor at the mercy of verbalism and would be subordinating substance to form.” It evolved in response to situations where accused infringers attempted to “practice a fraud on a patent” by introducing “minor variations to conceal and shelter the piracy.” Of course, the doctrine is in tension with the policy requiring that claims put the public on notice of a patent’s scope. This is a reason the Doctrine of Equivalents is not meant to be routinely invoked and is not applied broadly. In other words, this type of infringement is a limited exception to the general rule that patent claims must reasonably put others on notice of the outermost boundaries of what constitutes infringement. Put another way, it allows a limited form of “central” claim enforcement in a regime of “peripheral” claiming.
The Doctrine of Equivalents is applied individual claim limitations rather than to the claimed invention as a whole. To find infringement, each claim limitation (or element) must be found either literally or equivalently in the elements of accused product/process. This is called the “all elements” rule. The question of equivalence is inapplicable if a claim limitation is totally missing from an accused device. The Doctrine of Equivalents cannot be used to re-draft claims and effectively eliminate limitations entirely. Though this inquiry always revolves around what differences can reasonably be considered equivalent. An undue expansion of a patent’s claim(s) is not permitted. After-arising technology can potentially be encompassed by the Doctrine of Equivalents (unlike for means-plus-function equivalents).
There are two approaches to assessing equivalents: the “insubstantial differences” test and the “function-way-result” test. The function-way-result test (also called the “triple identity” test) says that equivalence may be present for a given element if the accused product/process performs substantially the same function in substantially the same way with substantially the same result. This is not the only way to assess whether differences are insubstantial, but it is particularly useful for certain types of inventions such as mechanical devices. For biochemical inventions, however, looking at substantial differences may sometimes be more appropriate than the function-way-results test.
There are numerous limits on the Doctrine of Equivalents, which are really beyond this basic introduction. But an extremely important limit on the availability of the Doctrine of Equivalents is prosecution history estoppel. Things that the patentee did or said when obtaining the asserted patent might limit the patentee’s ability to later rely on the Doctrine of Equivalents. So the Doctrine of Equivalents is not always or automatically available.
Indirect Infringement
Indirect patent infringement means that an accused party is causing or enabling someone else to infringe. It can apply when an accused infringer meets some but not all of the limitations (or elements) of an asserted patent claim. It includes three types of infringement, which differ in terms of what the accused indirect infringer is doing:
Supplying Component for Export for Combination Outside the USA (35 U.S.C. § 271(f))
Generally speaking, there are additional requirements that must be satisfied to establish indirect infringement that are not required for direct infringement. Those additional requirements vary depending on what type of indirect infringement is asserted.
Also, relevant limitations of asserted claim(s) can be assessed under either their literal scope or under the Doctrine of Equivalents, if available—see discussions above of literal and Doctrine of Equivalents infringement for direct infringement. This is really to say that the Doctrine of Equivalents may still apply to indirect infringement scenarios.
Active Inducement of Infringement
Actively inducing someone else to infringe a patent constitutes inducement of infringement. Specifically, “[w]hoever actively induces infringement of a patent shall be liable as an infringer.” (35 U.S.C. § 271(b)). This is a form of vicarious liability. Active inducement requires taking an affirmative steps to encourage infringement by another entity, as well as knowledge that the encouraged acts infringe the asserted patent. A key component of inducement is that it requires there be at least one direct infringer. But the difference here is that instead of suing the direct infringer, a different entity is sued for inducement.
Inducement commonly arises in situations involving claims to a method of using a product. Rather than sue the end user, which may be a potential customer, the patentee instead sues a competitor making and selling products used by others to (directly) perform and infringe the asserted method claim(s). It also sometimes arises where a corporate officer or owner induces his or her company to infringe, making that individual personally liable for infringement.
Contributory Infringement
Contributory infringement arises when selling, offering to sell, or importing components that are specially made or adapted for use to infringe a patent. However, contributory infringement excludes activities involving a staple article or commodity of commerce that is suitable for substantial noninfringing use. A “substantial noninfringing use” is any use that is not unusual, far-fetched, illusory, impractical, occasional, aberrant, or experimental. So there is normally no liability for selling general-purpose commodities, even if they could be used in making or using a patented invention.
“(c) Whoever offers to sell or sells within the United States or imports into the United States a component of a patented machine, manufacture, combination or composition, or a material or apparatus for use in practicing a patented process, constituting a material part of the invention, knowing the same to be especially made or especially adapted for use in an infringement of such patent, and not a staple article or commodity of commerce suitable for substantial noninfringing use, shall be liable as a contributory infringer.”
In order for contributory infringement to be present, the infringer must know that the combination for which his component was especially designed was both patented and infringing. This knowledge requirement differentiates contributory infringement from direct infringement, which does not require any such knowledge of the patent or infringement (except to enhance damages).
Contributory infringement is important for situations involving the sale of repair or replacement parts for use in or with patented products or methods.
Supplying Component for Export for Combination Outside the USA
Section 271(f) of the patent laws creates two grounds for infringement involving activities in the USA relating to products made in a foreign country. They arise when components of a patented invention are supplied for export from the USA. These grounds for infringement are similar to yet distinct from active inducement and contributory infringement, discussed above. But these provisions do not require that the equivalent of “foreign” direct infringement occur. That is, the actual combination need not actual occur. However, these provisions apply exclusively to apparatus claims, and are not available for method/process claims. They also do not apply to activities that occur entirely outside the USA. Also, § 271(f)(1) has a quantitative requirement about the number of components involved and it does not apply to only a single component.
“(f)
(1) Whoever without authority supplies or causes to be supplied in or from the United States all or a substantial portion of the components of a patented invention, where such components are uncombined in whole or in part, in such manner as to actively induce the combination of such components outside of the United States in a manner that would infringe the patent if such combination occurred within the United States, shall be liable as an infringer.
(2) Whoever without authority supplies or causes to be supplied in or from the United States any component of a patented invention that is especially made or especially adapted for use in the invention and not a staple article or commodity of commerce suitable for substantial noninfringing use, where such component is uncombined in whole or in part, knowing that such component is so made or adapted and intending that such component will be combined outside of the United States in a manner that would infringe the patent if such combination occurred within the United States, shall be liable as an infringer.”
The grounds for infringement under § 271(f) are somewhat rarely invoked. This is largely because manufacturing costs are often higher in the USA than abroad. As a result, courts have not extensively clarified the scope and proper application of these provisions. But suffice it to say they may apply in situations where components are being produced and/or sold in the USA for export.
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
Intellectual property (IP) litigation tends to be relatively expensive compared to other types of lawsuits. There are many reasons for that. Though the complexity of the legal issues involved and a tendency for extensive pre-trial discovery and use of expert witnesses contribute to the total costs.
Below are graphs showing average costs through various stages of a an infringement or misappropriation lawsuit in the U.S. A summary graph compares average costs for “small” patent, copyright, trademark, and trade secret cases with less than $1,000,000 at risk. There are also individual graphs for patent, copyright, trademark, and trade secret cases with different amounts at risk, that is, with different amounts of potential damages for infringement or misappropriation (in U.S. dollars). All data comes from the 2021 AIPLA Report of the Economic Survey.
Comparison of Average “Small” IP Lawsuit Costs by Type of Case and Stage
Average Patent Litigation CostsAverage Copyright Litigation Costs
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
Patent marking can be important for obtaining full recovery of infringement damages. When enforcing a patent against an infringer in the United States, damages for infringement of a patented article can usually be recovered only from the date the infringer had actual or constructive notice of the patent(s), whichever comes first. Actual notice requires the affirmative communication of a specific charge of infringement by the patentee to the accused infringer, such as in a cease-and-desist letter or filing an infringement lawsuit. Constructive notice is established by the patentee properly marking patented articles, regardless of whether a particular infringer actually sees that patent notice on products.
The following is a brief overview of basic U.S. patent marking legal requirements as well as guidance about how to properly implement patent marking. A more detailed treatment (with extensive examples) is provided in the Patent Marking Guide.
The U.S. Marking Requirement
The U.S. patent laws provide the following statutory marking requirement:
“Patentees, and persons making, offering for sale, or selling within the United States any patented article for or under them, or importing any patented article into the United States, may give notice to the public that the same is patented, either by fixing thereon the word ‘patent’ or the abbreviation ‘pat.’, together with the number of the patent, or by fixing thereon the word ‘patent’ or the abbreviation ‘pat.’ together with an address of a posting on the Internet, accessible to the public without charge for accessing the address, that associates the patented article with the number of the patent, or when, from the character of the article, this can not be done, by fixing to it, or to the package wherein one or more of them is contained, a label containing a like notice. In the event of failure so to mark, no damages shall be recovered by the patentee in any action for infringement, except on proof that the infringer was notified of the infringement and continued to infringe thereafter, in which event damages may be recovered only for infringement occurring after such notice. Filing of an action for infringement shall constitute such notice.”
These statutory marking requirements apply to all types of U.S. patents: utility, design, and plant. Having a marking requirement helps to avoid innocent infringement situations, among other things.
Patent Marking Provides Constructive Notice
Marking patented articles provides constructive notice to the public that an article is patented. To be legally sufficient to establish constructive notice, the patentee must be able to prove that substantially all of the patented articles being distributed were properly marked, and that once marking was begun, the marking was substantially consistent and continuous. If marking is defective at first, curing those defects going forward is possible. But full compliance with marking requirements to provide constructive notice to infringers is not achieved until the time the patentee consistently marked substantially all of the patented products, and if marking was deficient for a time then constructive notice will not be provided unless and until proper marking occurs with subsequent sales.
Possible Exceptions to Marking Requirements
The most important exception to the marking requirement is where the patentee has not sold any patented articles. When there are no products to mark, there is no failure to mark and therefore no bar to recovery of pre-suit damages.
Additionally, because the marking statute refers only to a “patented article”, patents with method or process claims are treated differently. Neither marking (constructive notice) nor actual notice is required to obtain back damages for infringement of asserted patents having only method or process claims. For patents having both apparatus and method claims, marking might still be required (if apparatus claims are asserted) and is therefore recommended.
Licensee(s) and Other Authorized Parties Must Mark Too
Marking requirements apply not only to the patentee but anyone making, selling, or offering for sale the patented article “for or under” the patentee or importing it into the U.S. Where a patent is licensed to another, expressly or impliedly, or is the subject of a covenant not to sue or the like, the other entity is required to mark as well. Authorized activities by an outsourced manufacturer or authorized seller are treated as if they are by the patentee in terms of marking requirements in this respect. Failure of a licensee or other authorized user to consistently mark substantially all licensed products will frustrate efforts to establish constructive notice. This requirement for licensees and authorized users is subject to a rule of reason. Some instances of omitted marking by others might be excused so long as the patentee makes reasonable efforts to ensure their compliance with marking requirements. It is recommended that any license for a U.S. patent obligate the licensee to comply with marking requirements. If that cannot be done, but a part (sub-component) is sold so that an authorized downstream reseller or importer will use it to assemble a patented article, that the part specifically intended for use in the patented combination carry a “for use under” patent marking notice.
How to Implement Patent Marking: Two Possibilities
There are two ways to mark patented articles in accordance with U.S. law: physical or virtual marking.
Physical Marking
Physical patent marking (which can also be called conventional or traditional marking) involves fixing notices on the patented articles themselves in a way that associates the patented article with the number of the patent. Such a notice must include the word “patent” or the abbreviation “pat.”, together with the number of the patent.
If the nature of the patented article means such a notice cannot be fixed to the patented article itself, such as due to size constraints or where the article is a fluid or powder, the notice can instead be placed on a label fixed either to the patented article or to a package containing one or more of the patented articles. This is an alternate form of physical marking that is appropriate if (and only if) there is a legitimate reason the marking notice cannot be directly fixed to the article. And that reason should involve more than mere convenience or subjective preference.
An example of a proper physical patent marking notice (for the fictitious U.S. Pat. No. 00,000,000) would be the following fixed directly on an article covered by the claims of the indicated patent:
Pat. 00,000,000
If multiple patents apply to the same patented article, they can be listed together. It is not necessary to repeat the word “patent” or abbreviation “pat.” before each patent number in such a list. Pluralizing the word “patent” is generally fine, as is the presence of an additional word or abbreviation, such as in “patent number 00,000,000” or “pat. nos. XX,XXX,XXX and YY,YYY,YYY”. The use of “U.S. patent” or “U.S. pat.” would also be acceptable. The text of the notice should be in English.
Virtual Marking
Virtual patent marking is an acceptable alternative to physical marking. It can be useful in situations where all the patent information required to provide constructive notice cannot easily fit on the patented article or even its label, such as where there are multiple patents that apply to an article that is fairly small in size. As the number of digits in patent numbers increase, this sort of difficulty increases. Virtual marking can also be helpful in situations where different patents are associated with different products but having multiple product-specific notices is burdensome—a single notice template might be used listing a URL for a web page with patent association information for multiple products. For instance, virtual marking can help minimize the need to replace or modify molds used to create a patent marking notice directly on molded articles as new patents issue.
Implementing virtual patent marking involves fixing notices on the patented articles themselves in a way that associates the patented article with the number of the patent. Such a virtual marking notice must use the word “patent” or the abbreviation “pat.” together with an address of a posting on the Internet (that is, a web page URL), accessible to the public without charge for accessing the address.
If the nature of the patented article makes means such a notice cannot be fixed to the patented article itself, the virtual marking notice (indicating “patent” or “pat.” together with a URL) can instead be placed on a label fixed either to the patented article or to a package containing one or more of the patented articles. This is an alternate form of virtual marking that is appropriate if (and only if) there is a legitimate reason the virtual marking notice cannot be directly fixed to the article. And that reason should involve more than mere convenience or subjective preference.
An example of a proper virtual patent marking notice fixed on a patented article or its label is the following:
Pat. www.example.com/patents
The main feature of virtual patent marking is that the information associating the patented article with the number(s) of the patent(s) that cover it appears on a freely-accessible web page rather than directly on the article or its label. There is still a requirement for a notice on the patented product or its label. A marking web page, alone, is insufficient unless there is also a proper notice on the patented product or its label to direct people to that web page’s address. Moreover, a virtual marking notice on a product or its package is insufficient without an acceptable posting accessible from the identified Internet address.
The difference between physical and virtual marking really involves the manner of conveying the required association between the patent number(s) and the patented article. With traditional physical patent marking, the association is implicit in terms of which patent numbers are including in or omitted from a notice fixed to a particular product or its label. In virtual marking, the notice fixed to the product or its label merely directs the public to a web page but the web page must further provide an association between given patent(s) and the specific product(s) that practice those patent(s).
Courts have said that virtual patent marking does not allow a patentee to avoid the traditional burden of determining which patent(s) apply to specific products and indicating that patent-to-product association. The patentee cannot shift that burden to the public. A web page that presents a “research project” forcing visitors to determine patent-to-product association(s) on their own fails to provide constructive notice. Any web page lacking the required “association” between the patent(s) and patented article(s) is legally deficient and will not provide constructive notice allowing recovery of pre-suit infringement damages.
Certain courts have found the following to be insufficient for virtual marking:
A web page listing all of a company’s patents with an indication that “one or more” listed patents “may be used” by unspecified products within a stated product category (cite)
A web page listing multiple patent numbers/titles and grouping them by product category, without indicating which specific products within each category were covered by specific patents (cite)
A table on a web page listing patent numbers and titles but lacking any product information (where the company sold multiple products and one was unrelated to its patents) (cite)
Patent-to-product associations indicated somewhere other than on the virtual patent marking web page (cite)
Failing to put a notice indicating a virtual marking URL on hardware sold by a licensee that had pre-installed software that made the combined hardware-plus-software product subject to an asserted patent (cite)
False Patent Marking Prohibited
An important related concept is false patent marking. False marking generally involves marking products as patented when they are not, or marking products as “patent pending” when no patent application has been filed, with an intent to deceive. It also applies to intentional counterfeiting. Penalties apply to intentional false marking (35 U.S.C. § 292). Although the patent laws exclude from the scope of false marking the indication of an expired patent that once applied to the marked product. Also, there is no liability for honest mistakes about whether or not a patent applies.
It is important to only use patent marking where there is a reasonable basis to believe that the product is covered by the indicated patent(s). Patents that do not apply to a given product must not be marked on it (consider also any invalidation or cancellation of a given patent for continued marking). In the virtual marking context, patent-to-product associations must be specific enough to avoid false marking. Imprecise, blanket statements on virtual marking web pages implicating multiple patents and multiple products might give rise to false marking if done for purposes of deceiving the public about which patents, if any, apply to particular products. More generally, avoid marking products with any “patented” language that is confusing, geographically vague, or misleading with respect to that product’s patent status in the USA.
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
There are many situations where it is desirable to challenge the validity or patentability of a granted patent or pending patent application. For instance, an invalidity search can be useful for an invalidity opinion to mitigate infringement liability, an invalidity defense in litigation, a proactive challenge to patentability at the U.S. Patent & Trademark Office (USPTO), or a pre-issuance submission (observations) to try to restrict or prevent a patent from being issued. But what is the best timing for such an invalidity search?
In one sense, an invalidity search is never strictly legally required. Though, practically speaking, invalidity searches are often crucial to avoiding or reducing liability for patent infringement in many contexts. These searches must be performed in a timely manner to obtain the greatest value from them. That includes performing searches in time to meet deadlines that require having suitable search results available.
Patent invalidity searches are reactive in the sense of being conducted in response to some infringement risk arising. That could be the receipt of a cease & desist letter, the filing of an infringement lawsuit against you, or other knowledge of a potentially problematic patent (e.g., via a freedom-to-operate study). In any event, an invalidity search requires first knowing which patent is the subject of the invalidity search. That is because an invalidity search depends on the scope of the particular claim(s) of concern and their effective filing date(s)—including any priority date(s).
It is a best practice to consider an invalidity search after a tangible risk of patent infringement comes to your attention. Knowledge of a patent coupled with a reasonable belief that infringement might be present can potentially give rise to enhanced damages for infringement. And knowledge of a pending patent application can potentially give rise to so-called “provisional rights” to pre-issuance infringement damages.
There may be deadlines that determine when invalidity search results are needed. For instance, in patent litigation in a district court, the court will issue a scheduling order that often sets a deadline to set for invalidity contentions. In is necessary to have search results available in order to formulate those invalidity contentions and prepare a suitable report. Other times, invalidity contentions might be requested through discovery requests, such as interrogatories. Either way, it is crucial to perform the invalidity search far enough in advance of such deadlines to allow for subsequent legal analysis of the search results.
Moreover, there are situations where a proactive challenge to a granted patent is desired. Proceedings such as inter partes review (IPR), post-grant review (PGR), oppositions, and the like may have various different deadlines by which a challenge must be filed. Such deadlines drive the timeline for completing invalidity searching. Just as in litigation, the search must be completed with time to spare to allow for legal analysis and preparation of any formal filing papers for the patent challenge, which may require considerable effort to prepare. Additionally, a pre-issuance submission (or observation) might be filed against a pending patent application and there likewise are both formal and practical deadlines to do so.
Lastly, if an opinion of counsel setting forth grounds for liability is desired to mitigate potential infringement damages, such an opinion should ideally be obtained before your relevant product (or process) is commercially launched. If patent in question is discovered only later, then such an opinion should be obtained without unreasonable delay. Having invalidity search results is a prerequisite to completing an invalidity opinion.
In all these possible settings, it is common for multiple invalidity searches to be performed. That can include follow-on invalidity searches performed in an iterative manner, in order to exhaustively locate prior art and to try to obtain sufficient prior art for desired (and reasonable) invalidity arguments as those arguments evolve and develop. It may also include searches performed by different searchers in different databases (including in non-patent literature databases), in different native languages, though investigation of prior public use and on-sale activities, and the like.
Have an invention you would like to patent? Have a brand you would like to register as a trademark? Concerned about infringing someone else’s intellectual property? Is someone else infringing your IP? Need representation in an IP dispute? Austen is a patent attorney / trademark attorney who can help. These and other IP issues are his area of expertise. Contact Austen today to discuss.
Is it possible for a U.S. design patent claim to include a negative limitation? It does not appear that courts have explicitly addressed this question. That is partly due to emphasis on design patent claims and infringement analyses revolving around the design as a whole, which can lead to rather conclusory decisions. But the question posed here is whether a claimed ornamental design as a whole can contain within it one or more “negative limitations” that effectively indicate the absence of some ornamental aspect, as opposed to indicating the positive (or affirmative) presence of an ornamental aspect. Certain past cases have touched on similar issues without specific reference to “negative limitations” in the sense that term is used with regard to utility patent claims.
Consider a design patent claim that shows as part of the overall ornamental design a flat surface, that is, a solid planar surface that is plain and uninterrupted. Does such a depiction include a negative limitation of sorts that excludes the presence of ornamentation on the surface? That is, does it give rise to a potentially significant overall difference when comparing a perforated surface or a surface that has substantial non-planar texturizing surface ornamentation? The same questions might arise, for instance, when a claimed design depicts only a single element (such as a single rounded corner, single support bar, single hole, etc.) but the accused product includes more than one of those elements.
In general, design patent infringement analysis involves two steps: (1) claim construction and (2) comparison of the properly construed claim to the accused product. Elmer v. ICC Fabricating, Inc., 67 F.3d 1571, 1577 (Fed. Cir. 1995). Theoretically, at least, questions about “negative limitations” in design patents could potentially arise in either of those two steps.
While, certainly, a jury can always reach an ultimate infringing/non-infringing conclusion, in the binary sense, based on the particular and specific facts at hand in any given case. But the topics at hand here are how courts should treat the legal issues surrounding how a finder of fact might be presented with design patent infringement questions where negative limitation issues are present, and also how courts making dismissal (Rule 12(b)(6)), summary judgment, judgment on the pleadings, judgment as a matter of law (JMOL), or appeal decisions can explain their reasoning under the ordinary observer test when negative limitations may be present.
Negative Limitations in Design Claim Construction
Design patent infringement analysis begins with claim construction. Although claim construction is also the first step in utility patent infringement analysis, design patent claim construction differs from that for utility patents in some important ways.
A patentable design “gives a peculiar or distinctive appearance to the manufacture, or article to which it may be applied, or to which it gives form.” Gorham Co. v. White, 81 U.S. (14 Wall.) 511, 525 (1871); see also Samsung Elecs. Co., Ltd. v. Apple Inc., 580 U.S. ___, 137 S. Ct. 429, 432-33 (2016). This means design patent claim construction must be adapted to the pictorial setting. Crocs, Inc. v. Int’l Trade Comm’n, 598 F.3d 1294, 1302 (Fed. Cir. 2010). In that sense, the Federal Circuit has said that “[d]epictions of the claimed design in words can easily distract from the proper infringement analysis of the ornamental patterns and drawings.” Id.; see also Dobson v. Dornan, 118 U.S. 10, 14 (1886) (a claimed design “is better represented by the photographic illustration than it could be by any description, and a description would probably not be intelligible without the illustration.”).
The Federal Circuit has cautioned that detailed verbal claim constructions increase “the risk of placing undue emphasis on particular features of the design and the risk that a finder of fact will focus on each individual described feature in the verbal description rather than on the design as a whole.” Egyptian Goddess, Inc. v. Swisa, Inc., 543 F.3d 665, 680 (Fed. Cir. 2008) (en banc). For such reasons, the level of detail to be used in describing the claimed design is a matter within a court’s discretion, and a court is not obligated to issue a detailed verbal description of the design if it would not be helpful. Id. at 679-80. Yet a court may use claim construction to help guide the fact finder through issues that bear on claim scope. Id. at 680.
Although not always at issue in every case, design patent claim construction can address prosecution history estoppel and prosecution history disclaimer. See Egyptian Goddess, 543 F.3d at 680. In general, the doctrine of prosecution history estoppel prevents a patentee from “recaptur[ing] in an infringement action the very subject matter surrendered as a condition of receiving the patent.” Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., Ltd., 535 U.S. 722, 734 (2002). It requires that “the claims of a patent be interpreted in light of the proceedings in the [US]PTO during the application process.” Id. at 733. The Federal Circuit has specifically held that prosecution history estoppel applies to design patents too. Pac. Coast Marine Windshields Ltd. v. Malibu Boats, LLC, 739 F.3d 694, 702 (Fed. Cir. 2014).
However, for design patents, unlike with utility patents, “the concepts of literal infringement and equivalents infringement are intertwined.” Id. at 700-01. Because it is the drawings of the design patent that provide the description of the invention, courts “look at the requisite drawings in design patents to determine whether a surrender has occurred.” Id. at 702. Estoppel arises when a narrowing amendment is made to satisfy any requirement to secure the grant of the patent, including amendments to avoid prior art or resulting from a restriction requirement. Id. at 703-04; see also Advantek Marketing Inc. v. Shanghai Walk-Long Tools Co., 898 F.3d 1210, 1216-17 (Fed. Cir. 2018).
In the Pacific Coast Marine Windshields case, a design application (for U.S. Des. Pat. No. D555,070) originally included drawings depicting—and claiming—multiple embodiments of a boat windshield. As reproduced below, the various originally-claimed embodiments showed the claimed windshield design with different vent hole configurations and also showed claimed designs that included and excluded a hatch on the front of the windshield. The examiner issued a five-way restriction requirement, identifying five distinct groups of designs as windshields with:
four circular holes and a hatch (FIG. 1);
four circular or square holes and no hatch (FIGS. 7 and 12);
no holes and a hatch (FIG. 8);
no holes and no hatch (FIG. 9); and
two oval or rectangular holes and a hatch (FIGS. 10 and 11).
Grid of selected original figures from the application for Des. Pat. No. D555,070
In that sense, the examiner indicated that many of the different embodiments (but not all of them) represented different design inventions. In response, the patentee removed alternate embodiments, thus deleting those alternate embodiments from the scope of the claim. That prosecution history had significant implications to the scope of the claim in the granted design patent before the court (D555,070). Incidentally, the patentee chose to file only one subsequent divisional application to the “no holes and a hatch” embodiment (that became U.S. Des. Pat. No. D569,782), apparently without pursuing any other of the original alternate embodiments—though a continuation application (that became U.S. Des. Pat. No. D593,024) based off the divisional was also later filed for a partial design to only the vertical corner posts with no vent holes (with the windscreen portions unclaimed, thus potentially avoiding hatch vs. no hatch questions).
Malibu Boats, LLC’s accused product (left) and FIG. 1 of U.S. Pat. No. D555,070 (right)
Noting that treatises and prior district court decisions had said similar things in the past, the Federal Circuit ruled that surrender of claims to the alternate designs was for reasons of patentability that caused prosecution history estoppel to attach. Pac. Coast Marine Windshields, 739 F.3d at 702-04. However, because the accused windshield product’s design had three vent holes (see above) but the patented design had four vent holes (see FIG. 1 above) and the surrendered embodiments/designs had only two vent holes (see original FIGS. 10 and 11 above), summary judgment of non-infringement was reversed and the case was remanded to the district court for further proceedings. Id. at 704-05. In other words, without reaching a definitive infringement/non-infringement decision, the patentee was barred from arguing that the design patent’s claim covered a two-hole design (or any other surrendered embodiments) but was still able to argue that a three-hole design might be covered because there was no surrendered three-hole embodiment in the original drawings. (The Federal Circuit decision did not address potential differences in the horizontal/angled frame or trim aspects of the accused design as part of the overall appearance analysis). After remand, and denial of subsequent summary judgment cross motions (which included inventorship disputes, and non-patent issues), the parties eventually settled.
Generally similar negative limitation issues have arisen in utility patent cases. For example, the Spine Solutions case involved questions of claim construction and prosecution history estoppel for a utility patent. Claim 1 of the patent in question recited “a single anchor on each of the upper surface of the upper part and the lower surface of the lower part . . . .” The relevant claim construction implicitly regarded the “single anchor” recitation as including a negative limitation, that is, requiring one anchor having the recited characteristics but excluding the presence of more than one anchor. There was no infringement by the accused device, which had two anchors rather than a “single” anchor as claimed. The Federal Circuit reasoned as follows:
“We agree with [the accused infringer] Medtronic that the court erred in determining that [the accused] O-Maverick [device] literally infringes claims 1 and 2. The [district] court construed ‘single anchor’ to mean, in relevant part, that ‘[t]he upper and lower surfaces of the implant each have one anchor having the characteristics recited in the last paragraph of [claim 1].’ Claim Construction Order, 2008 WL 4831770, at *14, 2008 U.S. Dist. LEXIS 116648, at *43 (emphasis added). A simple observation of [the accused] O-Maverick [device] confirms that the implant has two anchors on each of the upper and lower pieces, not one. The anchors are separated by a one-millimeter gap that extends all the way to the base of the implant; at no point are the two anchors joined or connected in any way. O-Maverick clearly has two anchors on each piece, not a ‘single anchor’ as recited by claims 1 and 2. Therefore, we hold as a matter of law that [the accused] O-Maverick [device] does not literally infringe claims 1 and 2.
“During prosecution, applicants expressly distinguished the claimed invention over the ‘477 patent by asserting that ‘a reference disclosing two anchors does not disclose a device affirmatively claiming a single anchor… reciting a negative limitation in the form of a single element is not disclosed by prior art which teaches more than one element.’ J.A. 17524. This is a clear disclaimer of claim scope, and prosecution history estoppel therefore bars [the patentee] SSI from arguing that a two-anchor device is equivalent to the claimed implant. Because we hold that [the accused] O-Maverick [device] is a two-anchor device, SSI cannot argue that O-Maverick infringes claims 1 and 2 under the doctrine of equivalents.”
What all these cases emphasize is that negative limitations can be at issue for design patent claim constructions, just as in utility patent cases. Prosecution disclaimer or prosecution estoppel issues resulting from arguments or amendments to a design application are especially relevant here. The Pacific Coast Marine Windshields case illustrates how those issues should be assessed as part of a design claim construction, if and when they arise. Other cases also indicated how this can be significant with respect to words in the design patent claim — such as words in the title that restrict the scope of the claim to a particular article of manufacture. Curver Luxembourg, SARL v. Home Expressions Inc., 938 F.3d 1334, 1340 (Fed. Cir. 2019); In re SurgiSil, L.L.P., No. 2020-1940 (Fed. Cir. Oct. 4, 2021). It is possible a design patent might include words like “individual” in the title that could include a negative limitation.
What is less certain for design patent claim construction is what role, if any, negative limitations have when the feature in question is something that appears in a drawing but there was no prosecution history disclaimer or estoppel. Because detailed design claim constructions that translate visual depictions into words are disfavored, it would not be appropriate in most situations to single out a particular visual element and explicitly construe it as containing a negative limitation (in the absence of a disclaimer or estoppel). That would depart from the context of the ordinary observer analysis and the requisite visual analysis of the overall appearance of the ornamental design.
Yet there may be instances where a negative limitation appears in relation to functional features, for example. The Federal Circuit has held that a claim construction may help the fact finder “distinguish[] between those features of the claimed design that are ornamental and those that are purely functional.” Egyptian Goddess, 543 F.3d at 680 (citing OddzOn Prods., 122 F.3d at 1405). A design may contain both functional and ornamental elements, even though the scope of a design patent claim “must be limited to the ornamental aspects of the design.” Ethicon Endo-Surgery, Inc. v. Covidien, Inc., 796 F.3d 1312, 1333 (Fed. Cir. 2015). “Where a design contains both functional and non-functional elements, the scope of the claim must be construed in order to identify the non-functional aspects of the design as shown in the patent.” OddzOn Prods., 122 F.3d at 1405; accord Ethicon Endo-Surgery, Inc., 796 F.3d at 1333. This ensures that the claim is limited to the ornamental aspects of the design, and does not extend to “the broader general design concept.” OddzOn Prods., Inc., 122 F.3d at 1405; see also Read Corp. v. Portec, Inc., 970 F.2d 816, 825 (Fed. Cir. 1992) (“[w]here . . . a design is composed of functional as well as ornamental features, to prove infringement a patent owner must establish that an ordinary person would be deceived by reason of the common features in the claimed and accused designs which are ornamental.”). But a construction of design features that are only partly functional, with some at least minimal ornamentation, must not entirely eliminate whole aspects from the scope of the claim, even as the functional elements limit and narrow the claim scope. See Sport Dimension, Inc. v. Coleman Co., Inc., 820 F.3d 1316, 1322-23 (Fed. Cir. 2016); Apple Inc. v. Samsung Elecs. Co., Ltd., 786 F.3d 983, 998-99 (Fed. Cir. 2015).
Negative Limitations in Comparisons Between Claimed Design and Accused Product
Following claim construction, if any, the design patent’s claim as construed is compared to the allegedly infringing products. Elmer, 67 F.3d at 1577. When considering infringement of a design patent, the “ordinary observer” test is the sole test for determining if infringement has occurred. Egyptian Goddess, 543 F.3d at 678 (rejecting the use of a separate “point of novelty” test); Crocs, 598 F.3d at 1303. Under the ordinary observer test, infringement occurs:
“if, in the eye of an ordinary observer, giving such attention as a purchaser usually gives, two designs are substantially the same, if the resemblance is such as to deceive such an observer, inducing him to purchase one supposing it to be the other, the first one patented is infringed by the other.”
Gorham, 81 U.S. at 528; Egyptian Goddess, 543 F.3d at 670-71.
This test has been codified in the patent laws, which provide as follows:
“Whoever during the term of a patent for a design, without license of the owner, (1) applies the patented design, or any colorable imitation thereof, to any article of manufacture for the purpose of sale, or (2) sells or exposes for sale any article of manufacture to which such design or colorable imitation has been applied shall be liable to the owner to the extent of his total profit, but not less than $250, recoverable in any United States district court having jurisdiction of the parties.”
35 U.S.C. § 289
Thus, as the ordinary observer test is sometimes described, infringement is not found unless the accused article embodies the patented design or any colorable imitation of it. Egyptian Goddess, 543 F.3d at 678 (citations omitted). Though recall that for design patents “the concepts of literal infringement and equivalents infringement are intertwined.” Pac. Coast Marine Windshields, 739 F.3d at 700-01.
Against that backdrop, the question of potential negative limitations can arise in the context of whether logos (or the like) present on the accused product can or should be considered when comparing it to the design patent claim to determine if there is infringement.
It is necessary to compare the claimed design (as construed) as a whole to accused product. Ethicon Endo‐Surgery, 796 F.3d at 1335; Crocs, 598 F.3d at 1302-06. This is to say that in the “ordinary observer” analysis, the patented design is viewed in its entirety, as it is claimed. L.A. Gear, Inc. v. Thom McAn Shoe Co., 988 F.2d 1117, 1125 (Fed. Cir. 1993). “[A]ll of the ornamental features illustrated in the figures must be considered in evaluating design patent infringement.” Contessa Food Prods., 282 F.3d at 1378. “A patented design is defined by the drawings in the patent, not just by one feature of the claimed design.” KeyStone Retaining Wall Sys., 997 F.2d at 1450. This means the comparison of the claimed design (as construed) to the accused product must generally include all of the patent figures in comparison, and it cannot merely compare separate elements in isolation or involve serial element-by-element comparison.
Yet an infringement analysis that recites significant differences between the ornamental features of the claimed and accused designs is still acceptable if, in determining infringement, that analysis still mainly focuses on whether an ordinary observer would be deceived into thinking that the accused product’s design was the same as the patented design. Richardson v. Stanley Works, Inc., 597 F.3d 1288, 1295-96 (Fed. Cir. 2010). It is in that sense that negative limitations can be used to help articulate significant differences from the standpoint of an ordinary observer.
Along those lines, the Federal Circuit has held that the finder of fact can consider “an ornamental logo, its placement, and its appearance as one among other potential differences between a patented design and an accused one.” Columbia Sportswear N. Am., Inc. v. Seirus Innovative Accessories, Inc., 942 F.3d 1119, 1131 (Fed. Cir. 2019). In a subsequent August 2021 trial under that guidance, a jury found no infringement. Columbia Sportswear N. Am., Inc. v. Seirus Innovative Accessories, Inc., No. 3:17-cv-01781 (S.D. Cal. Aug. 6, 2021) (jury verdict of non-infringement). The parties subsequently cross appealed.
In Columbia, the patent owner sometimes made a comparison of only a selected portion of the claimed design to the accused product in briefing. This had the effect of broadening the asserted claim. For instance, in the first comparative example below for district court summary judgment briefing, note how the claimed design uses broken lines in FIG. 1 to show that a boundary exists but is unclaimed (seeMPEP § 1503.02(III) (9th Ed., Rev. 10.2019, June 2020)). But the claimed design of FIG. 1 includes a generally sinusoidal wave pattern with four full crests and five full troughs that appear uninterrupted between the broken line boundaries; whereas in a comparison table used in briefing only part of the claim with merely three full (and uninterrupted) crests and troughs was reproduced as allegedly being the “Patented Design”. And in the second example below, from appellate briefing, note how FIG. 2 is used by the patentee for comparison despite the asserted design patent stating that “FIG. 2 is an enlarged elevational view thereof, taken from any area in the design” (that is, FIG. 2 merely shows an enlargement of a portion [with]in the claimed design but does not show the entire claimed design). If we analogize this to the utility patent context, it is like comparing a selected claim limitation to the accused product in isolation without addressing one or more additional limitations present in the claim. The significance of the accused product’s interruption (with repeating logos) in comparison to the claimed uninterrupted design was a key issue in the case including its appeals. So the question of what constitutes the full scope of the claimed design is foundational to what is or is not interrupted in the accused product.
FIG. 1 of U.S. Des. Pat. No. D657,093 (left) and Portion of Plaintiff Columbia’s March 7, 2016 Motion for Partial Summary Judgment (right)Portion of U.S. Des. Pat. No. D657,093 (left) and Portion of Plaintiff Columbia’s September 18, 2018 Appellate Response and Reply Brief Showing FIG. 2 of U.S. Des. Pat. No. D657,093 Overlaid on Photo of Accused Product (right)
The district court declined to construe the design patent claim with a detailed verbal description in its Markman order, or to provide any other construction or guidance about design patent conventions, but instead later provided jury instructions that stated:
“A design patent’s claim defines what is covered by the patent. The claim is typically represented by illustrations. It is permissible to illustrate more than one embodiment of a design in a single design patent application. Each design patent contains multiple drawings to illustrate the claimed design.
The scope of the claim encompasses the design’s visual appearance as a whole. It does not cover a general design concept and is not limited to isolated features of the drawings. An inventor’s subjective intent is not relevant to the scope of the claimed design”
Quote from Jury Instruction No. 9 (as filed Aug. 6, 2021)
That jury instruction (No. 9) was largely generic. It could have been issued in any design patent case without changing a word. Neither the jury instruction nor the Markman order specifically addressed the proper interpretation of the language describing FIG. 2 quoted above, which is part of the claim. Most significantly, the jury was not instructed to disregard the presence of logos on the accused product (as Columbia had sought). But, additionally, the jury was not instructed about whether the asserted design patent actually included multiple embodiments or whether certain drawings showed the same design or merely incomplete portions of it. That meant that, in the Columbia case, there was no express “negative limitation” claim construction. Instead, everything came down to the comparison of the overall appearances.
“To determine infringement of a design patent, you must compare the overall appearances of the accused design to the Design Patent. The accused design is Seirus’s HeatWave fabric. If you find by a preponderance of the evidence that the overall appearance of the accused design is substantially the same as the overall appearance of the Design Patent, you must find that the accused design infringed the Design Patent.
Two designs are substantially the same if, in the eye of an ordinary observer, giving such attention as a purchaser usually gives, the resemblance between the two designs is such as to deceive an ordinary observer, inducing him to purchase one supposing it to be the other. You do not need, however, to find that any purchasers were actually deceived or confused by the appearance of the accused products. You should consider any perceived similarities or differences between the patented and accused designs. Minor differences should not prevent a finding of infringement.”
Quote from Jury Instruction No. 10 (as filed Aug. 6, 2021)
The jury instruction (No. 10) regarding the comparison step did mention the accused product by name. But otherwise that instruction is also fairly generic. Jury instructions nos. 11-13 also pertained to design-patent-specific issues, including comments about the proper use of prior art in instruction no. 11.
The district court could have provided further claim construction guidance. But it chose not to. As already noted, the jury held that the patented design was not infringed. On the next appeal, there will surely be a dispute over the ultimate verdict of non-infringement of the design patent, but also perhaps about the mostly generic jury instructions related to design patent claim construction and infringement analysis and how those impact any “negative limitations” in the design patent claim. Though, interestingly, at the district court neither party really argued this point regarding the proposed final jury instructions for the August 2021 trial (most of the arguments over those instructions instead centered around what could be ignored, proper consideration of marketing materials evidence, how functionality should be referenced if at all, and the relevance and proper role of alleged prior art).
Conclusion
The appropriate way to address “negative limitations” in design patent claims is: first, to address in claim construction any prosecution history disclaimer or prosecution history estoppel issues that might give rise to recapture issues around such “negative limitations”, as well as any relevant interpretations of the text of the claim (including the title and description) that might do the same; and, second, to articulate the way design features affirmatively present in the accused design represent significant differences from such “negative limitations” in the claimed design in an analysis that still mainly focuses on whether an ordinary observer would be deceived into thinking that the accused product’s design was the same as the patented design overall.
The first aspect might not be relevant in all cases. Those questions will be highly dependent on the content of the asserted design patent claim and the prosecution history. But the second aspect could potentially apply whenever the asserted design patent appears to recite, in part, a “negative limitation”. This second part might impact jury instructions, as well as the way a case is argued to the finder of fact. It could also impact a pre-suit opinion of counsel analysis. Both factors might come up as part of dismissal, summary judgment, judgment on the pleadings, and/or JMOL motions, as well as in appeals.
January 2022
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
It may be desired to proactively challenge the validity or patentability of a granted U.S. patent for a variety of reasons. What are the available options to challenge a granted patent either at the U.S. Patent & Trademark Office (USPTO) or in court? The following table compares the different types of proceedings and summarizes the applicable standards.
Anyone with standing (substantial controversy between parties having adverse legal interests of sufficient immediacy and reality; requires affirmative act by patentee)
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
The Scope and Limits of Trade Dress and Patent Protection in Product Shapes: Food Product Case Studies
Intellectual property (IP) protection for product configurations of comestibles, confections, foodstuffs, and the like have been a matter of dispute in courts for well over a century. A variety of distinct IP rights may be invoked in this context, among them design patents and trade dress (either as a registered or unregistered trademark). Courts have grappled with the limits of such IP rights, seeking to prevent end-runs around the expiration of patent and copyright rights that the U.S. Constitution restricts to only limited times.[i] Such limits on IP rights embody long-standing Anglo-American legal principles in place since the Statute of Monopolies curbed the English Crown’s practice of granting “odious” monopolies over common commodities to raise funds or bestow favor.[ii] Cases up to the present highlight continued aggressive assertions of trade dress rights by foodstuff manufacturers—coupled with pushback by courts to deny trade dress rights in purely functional product configurations.
A number of important historical decisions observed the tendency for assertions of trade dress in (food) product configurations/shapes/forms/designs—these terms being used somewhat interchangeably—to inappropriately extend monopoly protections after a patent expired. Judge Learned Hand authored Shredded Wheat Co. v. Humphrey Cornell Co., which dealt with alleged trade dress infringement of the shape of shredded wheat biscuits after the expiration of a design patent to the same biscuit shape.[iii] He wrote that “the plaintiff’s formal dedication of the design [upon expiration of U.S. Des. Pat. No. 24,688] is conclusive reason against any injunction based upon the exclusive right to that form, however necessary the plaintiff may find it for its protection.”[iv]
Later, the Supreme Court weighed in on a dispute between Kellogg and Nabisco, finding the pillow shape of a shredded wheat biscuit to be functional because “the cost of the biscuit would be increased and its high quality lessened if some other form were substituted for the pillow-shape.”[v] The Court stated,
“The plaintiff has not the exclusive right to sell shredded wheat in the form of a pillow-shaped biscuit — the form in which the article became known to the public. That is the form in which shredded wheat was made under the basic [utility] patent [U.S. Pat. No. 548,086]. The patented machines used were designed to produce only the pillow-shaped biscuits. And a design patent [U.S. Des. Pat. No. 24,688] was taken out to cover the pillow-shaped form. Hence, upon expiration of the patents the form . . . was dedicated to the public.”[vi]
Kellogg has remained the touchstone for cases on the limits of trade dress protection, and not just for foodstuffs. Subsequent decisions have elaborated on the non-functionality doctrine without changing the basic framework.[vii]
In a more modern case, Sweet Street Desserts, a “Blossom Design” for a round, single-serving, fruit-filled pastry with six folds or petals of upturned dough was held to be functional and, accordingly, unprotectable as trade dress because the product’s size, shape, and six folds or petals of upturned dough were all essential to the product’s ability to function as a single-serving, fruit-filled dessert pastry.[viii] Only incidental, arbitrary, or ornamental product features that identify the product’s source are protectable as trade dress. Chudleigh’s trade dress Reg. No. 2,262,208 was cancelled.[ix]
In Ezaki Glico v. Lotte, the non-functionality requirement was assessed in connection with Ezaki Glico’s POCKY® treats—thin, rod- or stick-shaped cookies partially coated in chocolate (with optional nuts)—and Lotte’s competing PEPERO® treats.[x]
Ezaki Glico’s trade dress Reg. Nos. 1,527,208 (left) and 2,615,119 (right)Photos of original (left) and album (right) PEPERO® treats (for scale, these are about the size of a medium-length bamboo cooking skewer)
The core dispute was how to define “functional” for product configuration trade dress. Ezaki Glico argued a narrow reading, equating “functional” with “essential.” The court disagreed, reading Supreme Court precedent to say that product configuration features need only be useful to be functional. That is, a product shape feature is “useful” and thus “functional” if the product works better in that shape, including shape features that make a product cheaper or easier to make or use. The 3rd Circuit held that a product feature being “essential to the use or purpose of the article or if it affects the cost or quality of the article”[xi] is merely one way to establish functionality.[xii] A product feature is also unprotectably functional if exclusivity would put competitors at a significant, non-reputation-related disadvantage.[xiii] The rejection of a narrow reading of the functionality doctrine echoes cases in other circuits characterizing the Supreme Court’s TrafFix case as setting forth two ways to establish functionality.[xiv] There are several ways to establish functionality that are not limited to merely “essential” product features.
Functionality in the trade dress context is commonly assessed through the following types of non-dispositive evidence, as summarized in Ezaki Glico:
“First, evidence can directly show that a feature or design makes a product work better…. Second, it is ‘strong evidence’ of functionality that a product’s marketer touts a feature’s usefulness. Third, ‘[a] utility patent is strong evidence that the features therein claimed are functional.’ Fourth, if there are only a few ways to design a product, the design is functional. But the converse is not necessarily true: the existence of other workable designs is relevant evidence but not independently enough to make a design non-functional.”[xv]
There was evidence of practical functions of holding, eating, sharing, or packing the POCKY treats. Ezaki Glico’s internal documents showed a desire to have a portion of the stick uncoated by chocolate to serve as a handle. The court also noted how the size of the sticks allowed people to eat them without having to open their mouths wide and made it possible to place many sticks in a package. Ads for POCKY treats also emphasized the same useful features. Ezaki Glico proffered nine examples of partially chocolate-coated treats that do not look like POCKY treats, but the court found that evidence insufficient to avoid the conclusion that every aspect of POCKY treats is useful.
Finally, the court concluded that Ezaki Glico’s utility patent U.S. Pat. No. 8,778,428 for a “Stick-Shaped Snack and Method for Producing the Same” was irrelevant. The court’s rationale for that conclusion, however, is rather unconvincing. The utility patent was applied for in 2007, with a 2006 Japanese priority claim, which was long after Ezaki Glico began selling POCKY treats in the U.S. in 1978, and also long after Lotte began selling the accused PEPERO treats in 1983 and the first explicit allegations of misconduct in 1993. That patent was also still in force (i.e., unexpired). The utility patent corresponded to an “ultra thin” version of POCKY treats and Ezaki Glico argued that its patent addressed only one of many embodiments covered by its trade dress.
The lower court discussed utility patent disclosures regarding stick warping formulated like a problem-solution statement[xvi]—somewhat akin to inventive step (obviousness) analyses in European patent practice. But unmentioned was how the patent’s disclosed stick holder necessarily produces a partial chocolate coating.[xvii] The 3rd Circuit’s reasoning about the irrelevance of the utility patent is superficial to the point of being mere tautology. The appellate opinion did not address Kellogg’s statement that the form in which a food article was made under an expired “basic” patent was relevant to trade dress eligibility or other circuits’ cases that deemed a prior manufacturing method patent to be relevant. Moreover, the court did not address the way mere descriptiveness of just one good bars registration of a trademark for an entire group of goods encompassing additional, different goods.[xviii] Whether a later-filed patent can ever provide grounds to cancel an earlier trade dress registration for functionality is a question the court essentially avoided deciding.
Something else not discussed in Ezaki Glico was the 3rd Circuit’s decision nearly a century ago in the Eskimo Pie case.[xix] There, the validity of U.S. Pat. No. 1,404,539 on the original ESKIMO PIE® chocolate-covered ice cream treat was at issue. The court held the utility patent invalid, reasoning with regard to claim 6 (in which the core and casing form a “substantially rectangular solid adapted to maintain its original form during handling”) that “[t]here is no invention in merely changing the shape or form of an article without changing its function except in a design patent.”[xx] The rectangular solid shape was found non-functional and therefore unable to distinguish the prior art in a utility patent claim. The lower court had already pithily reached these same conclusions:
“The gist of the invention, if there be one, is in sealing a block of ice cream in a sustaining and self-retaining casing of chocolate. A rectangular piece of ice cream is coated with chocolate…. All that the patentee does is to take a small brick of ice cream and coat it with chocolate, just as candies are coated. [In the prior art,] Val Miller took a round ball of ice cream and coated it, just as candies are coated. In one case the ice cream is round in form, and in the other case it is rectangular. In both cases there is a sustaining and self-retaining casing, sealing the core of ice cream…. There is no invention in form alone.”[xxi]
U.S. Pat. No. 1,404,539
In a fascinating Wired article from 2015, Charles Duan located correspondence with the inventor’s patent attorney and other pertinent historical information in museum archives.[xxii] Duan highlighted how the invention, if anything, was really about the particular formulation of chocolate that allowed it to work effectively as a coating on a frozen ice cream treat, while the patent contains no disclosure in that regard and its claims were intended to be preemptive.[xxiii] Invalidation of the ESKIMO PIE patent opened the door for the KLONDIKE® ice cream treat, introduced in 1928, which was later the subject of an 11th Circuit trade dress case about product packaging (as opposed to product configuration) for a wrapper with a pebbled texture, images of a polar bear and sunburst, bright coloring, and square size that, in combination, were held non-functional.[xxiv]
Courts have tended to be more lenient on (food) packaging trade dress when it comes to functionality.[xxv] This held true when the 11th Circuit later found the unregistered product design of DIPPIN’ DOTS® multi-colored flash-frozen ice cream spheres/beads to be functional and thus ineligible for trade dress protection.[xxvi] An unexpired utility patent (U.S. Pat. No. 5,126,156)—later held invalid and unenforceable[xxvii]—was specifically cited as evidence of functionality of the product design, along with judicial notice that certain colors connote ice cream flavor.[xxviii]
So, in 1929, the 3rd Circuit ruled that the configuration of an ESKIMO PIE treat was ornamental and non-functional, and therefore unpatentable in a utility patent; whereas, in 2021, the Third Circuit ruled that the configuration of a POCKY treat was functional, and therefore ineligible for trade dress protection. How can these decisions be reconciled?
The only way to square these cases is to say that “functionality” in the trade dress context means something legally different than in the patent context. So, an ice cream treat’s shape/configuration was insufficiently functional to support a utility patent claim though a cookie treat’s shape and configuration was too functional (useful) to support trade dress protection. But courts and other commentators often stop well short of explaining why “functionality” differs in these two contexts, or what specific evidence would differ—aside from the separate need to prove inherent or acquired distinctiveness to establish trade dress rights.[xxix]
The ultimate conclusions in the two cases, however, are very consistent in seeking to limit overreaching IP assertions. The functionality doctrine for trade dress has long been used to scrutinize attempts to secure a potentially perpetual trademark monopoly on product feature(s) thatconsumers desire in the product itself apart from any unique but optional source-identifying function(s) of product configuration—as well as manufacturers’ concerns about ease and cost of manufacturability. In the patent context, utility requirements at least implicitly revolve around the technological arts rather than aesthetic, saleability, and product source identification concerns—those might be called functions but they are not the type of inventive functions that are eligible for utility patent protection.
But the courts have yet to make explicit the precise role, if any, of the relevant consumer’s perspective in this analysis, which would seem to be a legitimate inquiry in the trade dress context in a way it would not be in the utility patent context, for instance. Admittedly, the “ordinary observer” test used for infringement of design patents blurs this distinction somewhat, especially given that one appeals court has held that conflation of the trademark likelihood-of-confusion test and the design patent ordinary-observer test is harmless error.[xxx] But evidence of non-reputational consumer desires, such as a consumer survey or similar expert testimony, would appear to be rather unique to product configuration trade dress considerations and in closer cases might not always be answered or rendered unnecessary by the admissions or conduct of the alleged trade dress owner.
Certainly, many trade dress product configuration cases do turn on admissions or statements (such as ads) by the owner that indicate functionality or the failure of the owner to meaningfully rebut the persuasive articulation of functionality readily observable in the product itself. Additionally, parties aggressively enforcing trade dress have often also pursued or obtained another form of protection, such as a patent, and statements made in (or during the prosecution of) a patent on the same or similar subject matter can be relevant to trade dress functionality.[xxxi] The Supreme Court has gone so far as to explicitly note that invoking trademark rights as patent rights expire is suspicious enough to create “a strong implication” the party is seeking to improperly extend a patent monopoly and that summary disposition of anticompetitive strike suits is desirable.[xxxii] This means consumer surveys or the like should not become routinely necessary. Yet cases may arise where consumer perceptions of functionality (or usefulness) are not immediately apparent from the product configuration itself, or the plaintiff has not made damaging statements, making survey evidence informative in the absence of more straightforward grounds for assessing functionality. This seems like a potential additional (fifth) category of functionality evidence not spelled out in cases like Ezaki Glico.
Conclusion
Foodstuff product configuration trade dress disputes provide an excellent case study of how courts have sought to preserve consumer access to functional product features, as well as producer access to easy and economical manufacturing techniques. After all, the purpose of trademark law in general is supposed to be about helping consumers identify whether something originates from company A or company B, for instance, but it is not meant to give anyone a monopoly on that something itself. Unless product configurations are relatively easily avoided by competitors making basically the same products, assertions of trade dress protection in pure product configurations have often been rejected. While courts remain sensitive to potential confusion over a product’s source, valid product configuration trade dress rights, as a matter of branding, should include a prominent, non-functional feature related to reputation that does not significantly diminish consumer enjoyment or ease of manufacturability.[*]
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
[vii] See TrafFix Devices, Inc. v. Marketing Displays, Inc., 532 U.S. 23, 28-32 (2001); Wal-Mart Stores, Inc. v. Samara Brothers, Inc., 529 U.S. 205, 213-16 (2000); Qualitex Co. v. Jacobson Prods. Co., 514 U.S. 159, 164-65 (1995); Two Pesos, Inc. v. Taco Cabana, Inc., 505 U.S. 763, 771,775 (1992); Bonito Boats, Inc. v. Thunder Craft Boats, Inc., 489 U.S. 141 (1989); Inwood Labs., Inc. v. Ives Labs., Inc., 456 U.S. 844, 850 n.10 (1982); Sears, Roebuck & Co. v. Stiffel Co., 376 U.S. 225, 228-32 (1964); Compco Corp. v. Day-Brite Lighting, Inc., 376 U.S. 234, 238 (1964); see alsoScott Paper Co. v. Marcalus Mfg. Co., Inc., 326 U.S. 249, 255-57 (1945).
[viii] Sweet Street Desserts, Inc. v. Chudleigh’s Ltd., 69 F. Supp. 3d 530, 532-33 and 546-50 (E.D. Pa. 2014) aff’d 655 F. App’x 103 (3d Cir. 2016); see also 15 U.S.C. § 1064(3).
[ix] Sweet Street Desserts, Inc. v. Chudleigh’s Ltd., No. 5:12-cv-03363 (E.D. Pa. Jan. 15, 2015) aff’d 655 F. App’x 103.
[xi] Qualitex, 514 U.S. at 165 (quoting Inwood, 456 U.S. at 850, n.10).
[xii] Ezaki Glico, 986 F.3d at 257; accordPIM Brands Inc. v. Haribo of Am. Inc., No. 22-2821 (3d Cir. Sept. 7, 2023) (alleged trade dress of wedge shape and red/white/green color scheme made watermelon candy identifiable and reminiscent of a watermelon wedge and was therefore functional and unprotectable, with Principal Register registration ordered to be cancelled; “[f]unctionality is not a high bar” and “[e]ven if the design chosen both promotes a brand and also ‘makes a product work better,’ it is functional and unprotectable.” (citing Ezaki Glico, 986 F.3d at 258)); cf. Sulzer Mixpac AG v. A&N Trading Co., 988 F.3d 174, 182-84 (2d Cir. 2021) (color-coding to denote size of dental mixing tips improved the operation of the goods, which affects their quality, and therefore was functional and unprotectable as trade dress even though not essential).
[xiii] Ezaki Glico, 986 F.3d at 257 (quoting TrafFix, 532 U.S. at 32).
[xiv] Dippin’ Dots, Inc. v. Frosty Bites Dist., LLC, 369 F.3d 1197, 1203 (11th Cir. 2004); Groeneveld Transp. Efficiency, Inc. v. Lubecore Int’l, Inc., 730 F.3d 494, 506-09 (6th Cir. 2013); Schutte Bagclosures Inc. v. Kwik Lok Corp., 193 F. Supp. 3d 245, 261-62 (S.D.N.Y. 2016) aff’d 699 F. App’x 93, 94 (2d Cir. 2017).
[xvi] Ezaki Glico Kabushiki Kaisha v. Lotte Int’l Am. Corp., No. 2:15-cv-05477, 2019 WL 8405592 at *6 (D.N.J., 7/31/2019).
[xvii] See holder (61), which holds one end of stick-shaped pastries (40) while (only) the other end is immersed in a container (62) of liquid coating material (e.g., chocolate). U.S. Pat. No. 8,778,428, FIG. 5 and col. 5, lines 15-18 & 45-50.
[xviii] See TMEP §1209.01(b) (Oct. 2018).
[xix] Eskimo Pie Corp. v. Levous, 35 F.2d 120 (3d Cir. 1929).
[xx] Id. at 122; see also, e.g.,E.H. Tate Co. v. Jiffy Ents., Inc., 196 F. Supp. 286, 298 (E.D. Pa. 1961); James Heddon’s Sons v. Millsite Steel & Wire Works, 128 F.2d 6, 13 (6th Cir. 1942).
[xxi] Eskimo Pie Corp. v. Levous, 24 F.2d 599, 599-600 (D. N.J. 1928).
[xxiii] Id.; cf., Alice Corp. Pty. Ltd. v. CLS Bank Int’l, 573 U.S. 208, 223-24 (2014); Mayo Collab. Servs. v. Prometheus Labs, Inc., 566 U.S. 66, 72-73 (2012).
[xxiv] AmBrit, Inc. v. Kraft, Inc., 812 F.2d 1531, 1535-38 (11th Cir. 1986), cert. denied, 481 U.S. 1041 (1987), abrogated by Wal-Mart, 529 U.S. at 216, but see The Islay Co. v. Kraft, Inc., 619 F. Supp. 983, 990-92 (M.D. Fla. 1985).
[xxv] E.g., Spangler Candy Co. v. Tootsie Roll Inds., LLC, 372 F. Supp. 3d 588, 604 (N.D. Ohio 2019); Fiji Water Co., LLC v. Fiji Mineral Water USA, LLC, 741 F. Supp. 2d 1165, 1172-76 (C.D. Cal. 2010).
[xxvi] Dippin’ Dots, 369 F.3d at 1202-07; see also 15 U.S.C. §1125(a)(3). The court incorrectly stated unregistered product configuration trade dress can be inherently distinctive, a position abrogated by Wal-Mart.
[xxvii] Dippin’ Dots, Inc. v. Mosey., 476 F.3d 1337 (Fed. Cir. 2007).
[xxviii] Dippin’ Dots, 369 F.3d at 1205-06.
[xxix] See Keystone Mfg. Co., Inc. v. Jaccard Corp., No. 03-CV-648, 2007 WL 655758 (W.D.N.Y., Feb. 26, 2007).
[xxx] Unette Corp. v. Unit Pack Co., 785 F.2d 1026, 1029 (Fed. Cir. 1986); see also Converse, Inc. v. Int’l Trade Comm’n, 909 F.3d 1110, 1124 (Fed. Cir. 2018) (calling the standards “analogous”).
[xxxi] TrafFix, 532 U.S. at 29-32; Dippin’ Dots, 369 F.3d at 1205-06.
[xxxii] Singer Mfg. Co. v. June Mfg. Co., 163 U.S. 169, 181 (1896); Wal-Mart, 529 U.S. at 213-14; see alsoMorton Salt Co. v. G.S. Suppiger Co., 314 U.S. 488 (1942) (misuse of patent on machine to restrain unpatented salt tablet sales); Dastar Corp. v. Twentieth Century Fox Film Corp., 539 U.S. 23 (2003) (improper trademark law false designation of origin assertion after copyright expiration); EMI Catalogue P’ship v. Hill, Holliday, Connors, Cosmopulos, Inc., 228 F.3d 56, 63-54 (2d Cir. 2000) (“musical composition cannot be protected as its own trademark” because “[t]he creation and expression of an original work is protected by copyright law, and once an original work has been produced trademark law is not the proper means of protecting the rights in this originality”; declining to rule “that a product itself—in this case, the song—can serve as its own trademark”); Korzybski v. Underwood & Underwood, Inc., 36 F.2d 727, 728-29 (2d Cir. 1929) (election of protection doctrine bars copyright after obtaining patent: “An inventor who has applied for and obtained a patent cannot extend his monopoly by taking out a copyright . . . on what he has already diagrammatically disclosed”) accord Vacheron & Constantin-Le Coultre Watches, Inc. v. Benrus Watch Co., 260 F.2d 637, 642 (2d Cir. 1958) (“grant of a patent presupposed a dedication to the public of the disclosure, except so far as the statute specifically reserved it to the patentee”).
Under U.S. federal trademark law, a trademark registration can be refused or trademark infringement found if there is a likelihood of confusion. The “likelihood of confusion” standard covers more than identical uses, intentional copying, counterfeiting, and knock-offs. It is ultimately a question of determining what ordinary consumers understand and what would confuse them. Trademarks (and service marks) are intended to avoid consumer confusion about the source of commercially available goods and services. So these issues go to heart of trademark law.
Likelihood of confusion is a multi-factor analysis. There are a number of different facts that are taken into account in order to draw a legal conclusion about the likelihood an appreciable number of consumers would be confused. Each individual factor can point toward or away from confusion, or be neutral. Different factors can carry different weight in the overall analysis depending on the circumstances.
Keep in mind, however, that the likelihood of confusion analysis is about whether an appreciablenumber of ordinary consumers is likely to be confused. That a few undiscerning or careless prospective purchasers might occasionally be confused is not enough. There is generally no obligation under trademark laws to protect negligent, indifferent, inattentive, or careless purchasers from confusion or to make the market foolproof. The owner of a trademark is not entitled to a guarantee against confusion in the minds of careless and indifferent buyers. Even evidence of actual confusion among a few customers may be de minimis and not conclusive of likelihood of confusion.
A reliable consumer opinion survey is highly informative about likelihood of confusion. Actually, it is usually the best kind of evidence. But surveys are complicated and costly. The practical difficulty is to make a judgment about the likelihood of confusion without having survey results available.
A useful exercise is to try to envision a hypothetical consumer survey. This can help you be more objective and avoid looking at likelihood of confusion in too self-serving a way. Splitting hairs about insignificant differences is a common mistake. Thinking that established rights extend to any and all goods and services (that is, thinking that similar marks can never coexist) is also a common mistake. But turning to the idea of a hypothetical survey of ordinary consumers might help avoid those biases. Because, in the end, the likelihood of confusion question is about ordinary consumers’ perspectives not your own.
The specific list of factors considered is phrased in different ways by various courts and the U.S. Patent & Trademark Office (USPTO)—as discussed further below. But under the any formulation of likelihood of confusion factors, the overall analysis is similar. The marks do not have to be identical. Similarly, the respective goods/services do not have to be identical. It is sufficient that they are related in such a manner that an appreciable number of ordinary purchasers are likely to assume—mistakenly—that they originate from a common source.
Registrations at the USPTO
In the USPTO, six so-called DuPontfactors are used for the likelihood of confusion analysis. These DuPont factors can be used to refuse registration because there is a prior conflicting registration. They can also be used in deciding oppositions to applications and attempts to cancel an existing registration based on prior use of a mark. Two DuPont factors are always considered:
similarity or dissimilarity of the marks in their entireties as to appearance, sound, connotation, and commercial impression
relatedness of the goods or services as described in the application and prior application(s)/registration(s)
Four additional DuPont factors might also be considered, though there may not be any evidence available to allow consideration of these other factors:
similarity or dissimilarity of established, likely-to-continue trade channels (that is, actual sales methods used)
conditions under which and buyers to whom sales are made (for instance, “impulse” vs. careful, sophisticated purchasing)
number and nature of similar marks in use on similar goods or services
existence of a valid consent agreement between the applicant and the owner of the previously registered mark
The six factors listed above are actually a condensed list of the ones that are most commonly relevant in the examination of new applications. The DuPontcase actually set forth a total of thirteen factors. Though the other factors omitted from the condensed list above rarely come up except for certain contentious cancellation or opposition proceedings where an opposing party is involved, and even then may not be as significant as other factors.
The weight given to any of these individual factors can vary. There is no precise mathematical formula for how they are applied to reach a conclusion. Though the comparison always involves the specific mark and the specific goods or services identified in the application or registration in question. Actual uses of the mark in the marketplace that are not identified in the application or registration at hand are generally irrelevant—the USPTO only decides what can or cannot be registered. Questions about infringement are dealt with by courts instead.
The USPTO provides some useful hypothetical examples of likelihood of confusion comparisons.
Disputes in Court
Courts decide infringement allegations as well as issues about the validity of trademark rights. But there are slightly different formulations of the likelihood of confusion factors applied in courts from different parts of the country. So the applicable factors will depend on which “circuit” handles a given case.
For instance, in the 8th Circuit—whose jurisdiction covers the states of Minnesota, Iowa, Missouri, Arkansas, Nebraska, South Dakota, and North Dakota—six so-called SquirtCo factors are used to assess likelihood of confusion:
the strength of the owner’s mark
the similarity between the owner’s mark and the alleged infringer’s mark, based on an examination of the marks as a whole
competitive proximity (the degree to which the products compete with each other, though infringement may be found in the absence of direct competition)
the alleged infringer’s intent to “pass off” its goods as those of the trademark owner raises an inference of likelihood of confusion, but intent is not an element of a claim for trademark infringement
incidents of actual confusion (if any; not required to establish likelihood of confusion; requires more than isolated incidents of inattentiveness; its presence is also not conclusive of likelihood of confusion)
the type of product, its costs and conditions of purchase
The weight given to any of the factors for likelihood of confusion can vary. And there is no mathematical formula for applying them. Depending on the evidence available, some factors may be more important than others.
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
Recent Federal Circuit cases highlight a confused standard applied to discretionary enhanced damages determinations in patent infringement cases. As will be shown, the Federal Circuit has elevated the statement of mind requirement for enhanced patent damages contrary to Supreme Court precedent.
In Halo, the Supreme Court discussed how conventionally reckless conduct at the time of the conduct in question supports punitive damages for patent infringement under 35 U.S.C. § 284. Halo Elecs., Inc. v. Pulse Elecs., Inc., 979 U.S. ___, ___, 136 S. Ct. 1923, 1932-35 (2016) (“The principal problem with Seagate[] . . . is that it requires a finding of objective recklessness in every case before district courts may award enhanced damages. Such a threshold requirement excludes from discretionary punishment many of the most culpable offenders”). After-the-fact rationalizations drummed up during litigation were at odds with the conventional understanding of recklessness, which requires analysis of the accused’s state of mind at the time of the actions in question. Id. at 1930,1933. The Court clarified that “a person is reckless if he acts ‘knowing or having reason to know of facts which would lead a reasonable man to realize’ his actions are unreasonably risky.” Id. at 1933 (emphasis in original); cf. Sherry F. Kolb, “Why Can’t Jurors Distinguish ‘Knowing’ From ‘Reckless’ Misconduct?”Verdict (Jan. 11, 2012) (discussing subjective states of mind in the criminal law context, with helpful illustrative examples). “Section 284 allows district courts to punish the full range of culpable behavior[] . . . in a manner free from the inelastic constraints of the Seagate test.” Halo, 136 S. Ct. at 1933-34. In a way, Halo‘s ruling about conventional recklessness standards fits with other Supreme Court cases (like eBay v. MercExchange) striking down special rules and holding that patent matters are generally subject to the same standards that apply in other types of civil tort cases.
Since Halo, the Federal Circuit has been eager to restrict the Supreme Court’s holding to only a first step in a multipart analysis under § 284 despite the Supreme Court’s expansive discussion about “punish[ing]” the “full range of culpable behavior.” The Federal Circuit has, to some extent, lost the forest for the trees by focusing rather myopically on one sentence in Halo: “The subjective willfulness of a patent infringer, intentional or knowing, may warrant enhanced damages, without regard to whether his infringement was objectively reckless.” Id. at 1933. In doing so, Halo‘s ultimate holding that enhanced damages are available for conventional recklessness is lost.
The Federal Circuit currently maintains a two-step process for analysis of enhanced damages under 284. “[Halo] leaves in place our prior precedent that there is a right to a jury trial on the willfulness question. *** Whether the conduct is sufficiently egregious as to warrant enhancement and the amount of the enhancement that is appropriate are committed to the sound discretion of the district court.” WBIP, LLC v. Kohler Co., 829 F.3d 1317, 1341-42 (Fed. Cir. 2016). So, first, the finder-of-fact determines “willfulness” and, second, the court has discretion to impose enhanced damages, if any.
For the first step, the Federal Circuit has said that willfulness can be found if the accused infringer “acted despite a risk of infringement that was ‘ ‘either known or so obvious that it should have been known . . . .’ ‘ ” WesternGeco LLC v. ION Geophysical Corp., 837 F.3d 1358, 1362 (Fed. Cir. 2016) (emphasis added), reinstated 913 F.3d 1067, 1075 (Fed. Cir. 2019); accord Arctic Cat, Inc. v. Bombardier Recreational Prods. Inc., 876 F. 3d 1350, 1371 (Fed. Cir. 2017) (willfulness supported if accused infringer “actually knew or should have known that its actions constituted an unjustifiably high risk of infringement of a valid and enforceable patent.”). Halo used the phrase “having reason to know” while the Federal Circuit has, without explanation, instead used the phrase “should have known”.
The second step is a moral judgment that falls to the discretion of the district court. But enhanced damages do not automatically follow from a finding of willfulness. Halo, 136 S. Ct. at 1933 (“Yet none of this is to say that enhanced damages must follow a finding of egregious misconduct.”); see also Presidio Components, Inc. v. Am. Technical Ceramics Corp., 875 F.3d 1369, 1382 (Fed. Cir. 2017) (“an award of enhanced damages does not necessarily flow from a willfulness finding.”).
In Eko, the Federal Circuit ruled on jury instructions for willfulness. Eko Brands, LLC v. Adrian Rivera Maynez Enters., Inc., 946 F.3d 1367, 1377-79 (Fed. Cir. 2020). The most controversial passage in that opinion was the assertion that “[u]nder Halo, the concept of ‘willfulness’ requires a jury to find no more than deliberate or intentional infringement.” Id. at 1378 (emphasis added). Merely implicit in the court’s opinion is that the issue was a defendant challenging a jury instruction (based upon the Federal Circuit Bar Association’s (“FCBA’s”) National Patent Jury Instructions) upon which the jury found willful infringement. In other words, while the jury instruction may have omitted reckless conduct that Halo had found sufficient to support willfulness and enhanced damages, that point was moot and not at issue in the Eko appeal because the jury had found that even a heightened state of mind (beyond recklessness) was present. But the court’s reference to “no more than” deliberate or intentional conduct is the confusing part, because it is odd, to say the least, to describe a heightened intent standard with a phrase like “no more than” that normally connotes a low threshold.
Then the Federal Circuit offered a rationalization of Eko in SRI International. SRI Int’l, Inc. v. Cisco Sys., Inc., No. 20-1685, Slip. Op. at *9-10 (Fed. Cir., Sept. 28, 2021). There, a district court had noted that “the [Federal Circuit] is not entirely consistent in its use of adjectives to describe what is required for willfulness.” SRI Int’l, Inc. v. Cisco Sys., Inc. (SRI III), No. 13-1534, 2020 WL 1285915, at *1 n.1 (D. Del., Mar. 18, 2020). So the Federal Circuit responded: “To eliminate the confusion created by our reference to the language ‘wanton, malicious, and bad-faith’ in Halo, we clarify that it was not our intent to create a heightened requirement for willful infringement. Indeed, that sentence from Halo refers to ‘conduct warranting enhanced damages,’ not conduct warranting a finding of willfulness.” SRI Int’l, No. 20-1685, Slip. Op. at *9-10 (Fed. Cir., Sept. 28, 2021). This actually adds to rather than eliminates confusion, by emphasizing rather minor procedural points as a kind of shell game but doubling down on the aspect that runs contrary to recent Supreme Court precedent. The partial and selective quotation from Halo omits a number of grounds the Supreme Court held can support an award of enhanced damages. The relevant sentence in Halo reads in full: “The sort of conduct warranting enhanced damages has been variously described in our cases as willful, wanton, malicious, bad-faith, deliberate, consciously wrongful, flagrant, or — indeed — characteristic of a pirate.” Halo, 136 S. Ct. at 1932. Notice how the Federal Circuit’s quote drops the word “willful” and others? And recall from above how Halo was primarily about enhanced damages awards encompassing conventional recklessness?
The Disputed and Confusing Continuum of States of Mind for Willfulness and Enhanced Damages in Patent Cases, Before and After Halo
The visualization above is meant to show that there is a continuum of states of mind for “willfulness”, though there is a long line of cases from different areas of law that show that there is no definitive definition of how to describe “willful” intent in civil matters. Indeed, Justice Breyer’s concurrence in Halo noted that “‘[w]illfu[l]’ is a ‘word of many meanings whose construction is often dependent on the context in which it appears.'” Halo, 136 S. Ct. at 1936 (Breyer, J., concurring) (also contrasting behavior that is not “wanton” or “reckless”) (quoting Safeco Ins. Co. of Am. v. Burr,551 U.S. 47, 57 (2007), a case relied upon by the majority). Though it is indisputably clear that Halo found that conventional recklessness qualifies as willfulness for enhanced patent damages.
A typical description of recklessness is conscious and willful indifference to the risk imposed on the unlucky victim; not that the defendant intended to harm the victim, but that he knowingly imposed a risk on the victim, which could have been eliminated with minimum effort. See Anthony J. Sebok, “Purpose, Belief, and Recklessness: Pruning the ‘Restatement’ (Third)’s Definition of Intent,” 54 Vanderbilt Law Review 1165, 1177 (2001) (discussing punitive damages in product liability cases). Yet there is potential circularity in any continuum that would partly define one degree of “willfulness” in the patent context as “willful indifference”.
Despite argument over the proper descriptors of degrees of willful intent, the Supreme Court has said that these distinctions may be troublesome but are nonetheless necessary and that “the difference between one end of the spectrum—negligence—and the other—intent—is abundantly clear.” Daniels v. Williams, 474 U.S. 327, 334-35 (1986) (citing LeRoy Fibre Co. v. Chicago, M. & St. P. R. Co., 232 U.S. 340, 354 (1914) (Holmes, J., partially concurring) and O. Holmes, The Common Law 3 (1923)). But in Eko the Federal Circuit discusses only the opposite end of the spectrum from negligence and not the troublesome “middle” degrees of willful intent—namely the lowest degree of willful intent set forth in Halo: recklessness. In other areas of law, courts distinguish a “deliberate” state of mind as from a “reckless” one, with “deliberate” representing a higher degree of intent than “recklessness”. E.g., Express Scripts, Inc. v. Bracket Holdings Corp., 248 A.3d 824, 825 (Del. 2021) (“A deliberate state of mind is a different kettle of fish than a reckless one.”). It is problematic, to say the least, for the Federal Circuit to sidestep entirely these troublesome but necessary distinctions in degree by using terminology like “deliberate” and “intentional” that typically connotes a higher degree of intent than the recklessness standard set forth in Halo.
Further complicating matters is that the Federal Circuit has taken a contradictory position about what “should have known” means in patent and trademark cases. Sometimes the Federal Circuit says “should have known” means negligence while at other times appears to say it means recklessness. For instance, more than a decade ago it clarified the requirements to establish when fraud on the USPTO bars trademark registration. The Federal Circuit rejected the TTAB’s “should have known” fraud standard because it — supposedly — correlates to mere negligence. In re Bose Corp., 580 F.3d 1240, 1244 (Fed. Cir. 2009) (“[B]y equating ‘should have known’ with a subjective intent,” the TTAB “erroneously lowered the fraud standard to a simple negligence standard.”). The Federal Circuit has also interpreted “should have known” as equating to negligence in patent cases involving active inducement of infringement. And yet, in WesternGeco and Arctic Cat the Federal Circuit held that “should have known” is an appropriate standard for willfulness in patent cases under Halo. And Halo made clear that “a person is reckless if he acts ‘knowing or having reason to know of facts which would lead a reasonable man to realize’ his actions are unreasonably risky” and that such recklessness is sufficient to award enhanced damages. Halo, 136 S. Ct. at 1933; see alsoMotiva Patents, LLC v. Sony Corp., 408 F. Supp. 3d 819, 837 (E.D. Tex. 2019) (“Halo holds that recklessness alone is enough to show willful infringement.”).
Halo abrogated at least the “inelastic” part of Seagate that set the threshold for willfulness and enhanced damages too high because if failed to allow enhancement for conventional (subjective) reckless intent at the time of the conduct at issue. Now (since Eko and SRI), the Federal Circuit has seemingly done an end-run around Halo by requiring an elevated level of intent beyond recklessness in order to support discretionary “enhanced damages” following a finding of willfulness. An issue here is that Halo said, “Consistent with nearly two centuries of enhanced damages under patent law, however, such punishment should generally be reserved for egregious cases typified by willful misconduct.” Halo, 136 S. Ct. at 1933-34. But recent Federal Circuit cases make no reference to that nearly two century history and instead utilize rather tendentious, selective, and partial quotations from Halo suggesting that a heightened state of mind beyond conventional recklessness is required for enhancement following a willfulness determination (contrary to the holding in Halo).
In the past, the Federal Circuit said that willfulness and discretionary enhancement analyses were basically the same. E.g., SRI Int’l, Inc. v. Advanced Tech. Labs., Inc., 127 F.3d 1462, 1469 (Fed. Cir. 1997) (“The principal considerations in enhancement of damages are the same as those of the willfulness determination, but in greater nuance as may affect the degree of enhancement.”). The Read factors commonly used for these analyses were about the totality of the circumstances and did not draw any categorical distinctions between degrees of intent within the category of willfulness (e.g., between recklessness and knowing/deliberate states of mind). Now, the Federal Circuit seems to be heading in another direction with (purportedly) a different standard for discretionary enhancement than for willfulness determinations. See Ryan Davis, “Fed. Circ. Outlines Willfulness, Enhanced Damages Standards,”Law360 (Oct. 7, 2021).
So today patentees face a situation in which the Federal Circuit seems to have merely pushed the abrogated initially high (“objective recklessness”) threshold of Seagate to the back end of the discretionary enhanced damages analysis, with what looks unmistakably like a heightened subjective intent requirement—higher than, and contrary to, the conventional recklessness standard set forth in Halo. Though another way to look at this is to say that the Federal Circuit has actually heightened the threshold “willfulness” standard too, even though they deny doing so, because a “deliberate or intentional” requirement has long been considered a heightened level of intent compared to conventional recklessness. Either way, this seems to shield merely reckless conduct from punishment, contrary to Halo, and is an untenable position for the Federal Circuit that calls for either an en banc reversal or further action by the Supreme Court.
P.S. — I should have a magazine article forthcoming in mid-2022 dealing with willfulness/enhanced damages. It will discuss the way district courts have frequently overlooked (or even ruled contrary to) 35 U.S.C. § 298 when dealing with issues involving the minimum requirements for willfulness and the way some district court cases (not yet reached in any precedential Federal Circuit decision) seem to resurrect something that looks like the old, abrogated “duty of due care” standard that corresponded to mere negligence.
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
Reproduced here are materials presented at the AIPLA CLE webinar “Patent Searching: (Almost) Everything You Need to Know“ on September 14, 2021. The presentation slides, which include links to patent searching resources available online, are available for download below.
Rather than a tutorial or “how-to” guide in the mechanics of searching, these program materials address important considerations that inform the planning, execution, and validation of all types of patent searches, including patentability, freedom-to-operate, invalidity, landscape, and due diligence searches. Readers will learn about timing considerations, budgeting and staffing models, export controls, privileges, evidentiary considerations for invalidity/patentability challenges, metrics for evaluating the effectiveness of a search, and more. This overview will be useful for those who perform searches themselves and those who outsource their searches to others.
I. Types of Patent Searches
A. Landscape/State-of-the-Art Search
The purpose of a patent “landscape” search is to ascertain the overall state of patents in a particular technology area. While “state-of-the-art” is sometimes used synonymously with “landscape” here, a distinction can be drawn between a patent landscape search limited exclusively to patents and published patent applications and a state-of-the-art search that includes patent documents as well as non-patent publications and potentially also commercially-available products. These searches are frequently used for competitive/business intelligence purposes. Landscape searches may be limited to particular jurisdictions in some cases. Reports and documentation for landscape searches are often focused on only high-level bibliographic information and the like and may omit detailed discussion of the content of specific patent claims. Landscape search reports can be very basic but also can be highly elaborate with infographics and other more elaborate visual elements aimed at an audience of businesspeople—especially higher-level executives—rather than patent attorneys.
Landscape searches are exploratory searches performed for business-related purposes and they are not legally required.
B. Patentability Search
A patentability search identifies potential prior art against a particular invention, and is performed in order to assess the likelihood that a patent would be granted on the invention and the potential scope of allowable/patentable subject matter. They allow more informed judgments as to whether the costs and effort of a patent application will be worthwhile. Results of a patentability search can also be utilized by the person(s) preparing a patent application on the invention to improve the quality of the application through better awareness of the closest prior art.[1] The patentability search, as such, is the gathering of relevant prior art for purposes of a patentability analysis, which involves legal judgments beyond mere searching effort.
The scope of a patentability search may be based on the contents of an invention disclosure document; changes or further developments to the invention that are not contained in such a document—or are simply not explicitly identified in a meaningful way—may not be captured by the search. Patentability searches should capture disclosures contained anywhere in a given prior art document or product, including inherent disclosures and things visible only in the drawings. Patentability searches ideally encompass both patent documents and non-patent publications, as well as commercially available products, available anywhere in the world. However, as a practical matter, patentability searches are usually subject to significant constraints on their scope. Most patentability searches are budget-constrained, whether in terms of a monetary budget or a time budget (e.g., needed by tomorrow). Moreover, some patentability searches might be limited to only a search of patent documents, or in a database that covers only certain key jurisdictions or non-patent literature (NPL) publications.
Patentability searches are exploratory searches performed to enable a legal evaluation of patentability as well as to inform business decision-making but they are not legally required by the USPTO before filing a patent application. Sometimes a patentability search is combined with a freedom-to-operate (FTO) search.
C. Due Diligence Search
Due diligence searches are performed in various contexts where it is desired to verify the current ownership/assignment of given patent(s) or application(s) and to identify potential clouds on title, to establish family and other bibliographic data, and to vet corporate mergers & acquisitions (M&A) that involve patent assets and other patent licensing or acquisition opportunities (e.g., to assess scope, validity, valuation). In the due diligence context, searching may be focused on ascertaining ancillary data for a known or limited universe of patents. Due diligence searches may shade into other types of searches. For instance, a freedom-to-operate search may be performed to assess infringement risks associated with a product line or technology acquisition. Also, sometimes invalidity searches are performed during acquisitions in order to assess the strength of acquisition targets or even to proactively attack the patents to create leverage to drive down acquisition cost. Another situation where due diligence searches can be utilized is in preparation for enforcement.
Due diligence searches can be considered exploratory searches. There is generally no affirmative legal duty to perform a due diligence patent search.[2]
D. Freedom-to-Operate (FTO)/Clearance/Right-to-Use Search
An FTO search, also called a “clearance” or “right-to-use” search, is used to identify patents and pending patent applications that pose potential infringement risks associated with a particular product or process.[3] “Contract clearance” searches are a subset of FTO searches for compliance with contract provisions. The FTO search, as such, is the gathering of relevant patents and applications for purposes of an FTO analysis, which involves legal judgments beyond mere searching effort.
The scope of an FTO search must generally first be ascertained by performing a “feature identification” or “product decomposition” analysis to identify discrete, potentially patentable features to be searched. FTO searches focus on the claimed subject matter, and need not address non-patent materials. Moreover, FTO searches may be limited to only jurisdictions where the product or process will be made, used, sold, or offered for sale—bearing in mind that contributory or induced infringement risks may expand the list of relevant jurisdictions in some situations.
In order to have a reasonable basis to rule out potential infringement risks an FTO search must be reasonably comprehensive and reliable, meaning that FTO searches should ideally not be subject to arbitrary constraints. Though in some situations an FTO search on particular feature(s) might be deferred or foregone if there is a reasonable basis to believe those feature(s) will present relatively low risk of infringement, such as where the particular feature of the product or process in question is confidently known to have been in commercial use (identically) for more than twenty years—making any recent patents directed to such a feature likely to be invalid.
FTO searches are defensive searches performed to enable a legal evaluation of infringement risk. Sometimes an FTO search is combined with a patentability or due diligence search. A potential infringer is not subject to an adverse inference for failing to affirmatively conduct an FTO search and/or seek an opinion of counsel.[4] Though the range of options to avoid liability is much greater if you find a potentially problematic patent before it finds you.
E. Invalidity/Unpatentability/Nullity/Opposition Search
An invalidity search is used to identify prior art that renders one or more claims of a given patent invalid. Invalidity searches are often used to develop an invalidity defense to an allegation of infringement and/or to help establish a good faith belief in invalidity to avoid a charge of willful infringement through an advice of counsel defense.[5] Depending on the context, such as for a challenge at the USPTO, the word “unpatentability” may apply instead of “invalidity”, in a strict sense. In other countries, terms like “nullity” or “opposition” might be used instead of “invalidity” or “unpatentability”. An invalidity/unpatentability search can further be used to identify prior art against one or more claims of a pending patent application, for potential use for a third-party pre-grant submission or third-party observations made to the relevant patent office.
Invalidity searches should seek relevant disclosures contained anywhere in prior art documents or products, including inherent disclosures and things visible only in the drawings. Invalidity searches ideally encompass both patent documents and non-patent publications, as well as commercially available products, available anywhere in the world. Though the status of certain activities or documents as “prior art” may vary. Research into commercially available products may take on the character of an investigation more than an exercise in database searching. Because invalidity searches may be performed in high-stakes situations, they are often the most involved and comprehensive searches, because the extra effort and expense is justified. For example, it may sometimes be worthwhile to commission multiple invalidity searches in different languages.
Invalidity searches are defensive searches performed to enable a legal defense to be developed against an actual or potential allegation of infringement. Although invalidity searches are not legally mandated per se, they are generally necessary in a practical sense in order to develop and assert an invalidity defense or affirmatively challenge validity/patentability.[6]
II. Timelines
Searches can be informally divided into two general categories: prospective and reactive.
Prospective searches include landscape, patentability, and FTO searches. The prospective category refers to a given search being performed in advance of some key decision point or action, such as before the launch of a product (FTO search), or the preparation and filing of a patent application (patentability). Prospective searches inform such decisions and actions and, accordingly, should be timed so that completed search results are available to be analyzed prior to any deadlines for a decision or action.
With respect to FTO searches, in particular, searching may be performed on an ongoing or periodic basis, such as to monitor patenting activity by particular competitor(s) and/or in particular technology area(s). Additionally, there may be a need to watch the prosecution status of certain pending patent applications, to ascertain the scope of what, if anything, is later allowed or granted. Some patent database tools include features to help facilitate various ongoing monitoring efforts. Furthermore, FTO searches may need to be updated at a later point in time. For instance, changes in product configuration may arise (e.g., manufacturability concerns arise close to a schedule product release that prompt a slightly different product configuration, or a new version of a product is developed years later) and require a new search—or at least a renewed analysis of existing search results. Additionally, because patent applications are typically published 18 months from filing, though potentially only upon grant, at the time of any given FTO search there may be relevant but unpublished patent applications pending that can only be captured by a subsequent search.
Invalidity and due diligence searches are reactive, in the sense that they are performed after some concrete or potential infringement risk comes to light or some need for confirmation arises. There may still be deadlines for filing an answer to a complaint before a district court, filing a patent office challenge (e.g.,PGR, IPR, opposition, observation), completing an M&A deal, or the like that constrains aspects of an invalidity search timeline. One benefit of conducting FTO studies is that early identification of potentially problematic patents can help provide a longer time period for invalidity searching.
III. Budgeting and Staffing
In the most general sense, patent searches are about solving information-retrieval problems. While it is always (theoretically) desirable to conduct a “perfect” search, with hypothetical 100% recall and 100% precision, in the real world all searches are subject to constraints and a “perfect” search is not possible. Those constraints may be in the form of deadlines or budget limits. For instance, few if any patentability searches have an unlimited budget, and most operate on the premise of making reasonable efforts within some predetermined time and budget limits. Any given search also usually includes express or implied limits on the databases, jurisdictions, and languages in which a search is conducted.
The project management discipline has developed something called the “iron triangle”, which can be applied to the searching context. In its most basic form, the “iron triangle” has three components: cost, speed, and quality. Project management says you must pick only two of the three on any given project—you cannot have all three, even though those requesting searches often want all three.[7] But the two factors selected will generally vary depending on the type of search, with patentability searches often sacrificing quality in order to achieve cost and speed objectives and with FTO and invalidity searches accepting slower timelines and/or greater costs in order to maintain high quality, for example. Also note that if you do not pick two of the three, someone else will pick them for you.
For any given search, the amount of effort required varies depending on the density of patenting or publication in a given technology area. Though at the beginning of a search that density may be unknown—usually this is only something that can be estimated well if numerous searches have previously been performed on related subject matter.
Continuums of Patent/Publication Density and Searching Cost/Effort
Searches can be performed by dedicated non-attorney searchers. Though attorneys can perform searches themselves and it may be surprising to some that attorney-conducted searches may be more cost effective in some situations because legal analysis and searching per se can be done concurrently and features of search tools can help aid the legal analysis (e.g., by informing the attorney which particular keyword(s) returned a given reference and highlighting that term in a searchable document). Prize/award-based “crowdsourcing” is another approach, usually best suited to invalidity searches.
When retaining a person or firm to conduct a search, another common decision point is choosing between an experienced subject-matter expert (e.g., an in-house staff person) versus a “hired gun” (e.g., a professional searcher with little or no knowledge of the specific subject matter). Because experience has a cost this is generally a cost vs. quality tradeoff.
Export controls and similar provisions (e.g., ITAR, sanctions, DoD tranches) may prohibit (or limit) who can perform a given search, which may prohibit outsourcing a search abroad.[8] For conventional export controls, the Commerce Control Lists (CCLs) establish what is subject to export restrictions. The “EAR99” CCL designation generally applies to low-tech consumer goods that do not require export license in many situations. However, “dual-use” export controls apply to things that have both military and non-military applications, and can be esoteric. The Wassenaar Arrangement Control Lists also provide guidance on what is currently implicated by dual-use export controls. Reexports and retransfers are also prohibited.[9] As an example of reexport, consider that a person from a foreign country sends technical information to a searcher in the USA; the searcher may not be able to send (reexport) the same information back to that same person—here you can think of the USA like a “fly trap” for export-controlled information. Lastly, even if you are operating entirely within the USA, a “deemed export” involves providing controlled information to a non-Green Card foreigner (or non-protected person) located in the USA. That is, providing information to a foreigner physically located in the USA is “deemed” to be the same as exporting that information to the foreigner’s home country.
IV. Resources for Conducting Searches
A. Introduction
It is often said that patent searching is more an art than a science. There is no one-size-fits-all formula for conducting effective and reliable searches. While searching does not become “easy” simply because you wish it was easy, and there is a learning curve, it is a skill that can be learned. Fortunately, there are many resources available on the mechanics of how to conduct searches in the patent context.[10]
There are many patent searching tools available, most of which are computer databases accessible via the Internet, though patent offices and affiliated libraries do offer some additional on-site-only resources for patent searching.[11] Search engine functionality varies widely, with advanced features like proximity searching, bulk export of selected data, and highlighting of keywords within search results available only with certain tools. In general, paywalled proprietary databases tend to have bells and whistles that can be helpful and save time. Though user licenses can be significant and searchers who perform searches only occasionally will likely find yearly license fees cost-prohibitive.
Whatever particular tool is used it is important to familiarize oneself with the scope of coverage (which jurisdictions are covered? what time periods are full-text searchable?) and the database’s search syntax, which refers to the particular operators used to command the search engine to run queries in particular ways. While basic Boolean operators like “AND” and “OR” tend to be fairly universal, some tools require those operators to be in all caps. More advanced operators like proximity commands or wildcard characters can be very different from one tool to the next. Search syntax matters because a given search string or query inputted verbatim into different database tools may be parsed quite differently.
B. Principal Database Searching Methods
While it is still possible to search for information by visiting a library and locating relevant physical publications, most patent-related searching today is performed using computer databases, most of which are now accessible via the Internet. Computer databases useful for patent searches can be queried in a number of different ways that are ultimately a function of both the database’s search engine and metadata structure and content.
Keyword searching, which is generally synonymous with Boolean searching, involves inputting keywords and Boolean operators (“AND”, “OR”, etc.) into a keyword string or query that the database’s search engine parses against its contents. Database search engines have vastly different capabilities. For instance, proximity operators are available with some databases that can be used to greatly increase the precision of keyword-based queries. Moreover, some databases are only full-text searchable back to a particular historical date. But be aware that not all databases or search engines are perfect, even the most full-featured tools. A database populated by text obtained through optical character recognition (OCR) may contain errors that frustrate efforts to use the database’s search engine. Databases that utilize machine translations of foreign patent documents for search queries may produce unreliable or unexpected machine translations in some instances. Also, and perhaps less widely known, is that database providers may parse keyword strings in ways that deviate from what a searcher has inputted in given query. For instance, in order to manage server computer hardware loads, to “enhance” searches, or for another reason, some search engines will include automatic thesaurus and/or pluralization functions or will parse defined phrases with spaces in between characters or as proximity searches (without the user inputting proximity operators). Such features may increase recall but at the same time may decrease precision. Conversely, some search engines may limit proximity searches to individual paragraphs, omitting from search results the presents of terms that are as proximate as specified but in two different paragraphs, which may reduce recall. Thesaurus functions can be helpful but cannot be relied upon exclusively. Not only are the thesaurus lists generally hidden within a “black box” of the database software, but they often are inadequate to capture variations in technical terms used in the patent context. For instance, an automatic thesaurus is unlikely to recognize that while “shopping cart” is a term used commonly in the USA, in Great Britain and Australia the term “shopping trolley” is used instead, or be able to ascertain whether “backhoe” and “excavator” are synonyms within the context of a given patent search. Translations can also be a factor here. For that matter, patentees can act as their own lexicographer. So, a search for automatic license/number plate recognition (ALPR/ANPR) tools using conventional terminology may not locate a patent that describes such a tool as a “parkulator” (a completely invented word).[12]
Classificationsearching involves reviewing patent documents according to subject-matter classifications made by patent offices. Historically, before the advent of computerized databases, searching hard copies of patent documents by classification (stored in “shoes” at the USPTO) was the only way to search patents. Today, there are a number of different classification systems currently in use, as well as ones that are no longer in use but can still be utilized in some situations. The main classification systems currently in use are the International Patent Classification (IPC) system, the Cooperative Patent Classification (CPC) system, the Japanese File Index/Facet (FI) and File Forming Term (F-term) systems, and the Locarno system for design patents (and industrial designs). The main discontinued classifications that may still have some value are the U.S. Patent Classification (USPC) system and the European Patent Classification (EPC) system, both of which were retired by the end of 2014. While patent offices have made efforts to re-classify old patent documents under the current classification systems, the nature of differences between the old and new classification systems means that there is at most a statistical correspondence between the two that varies for different subject matter areas.
In general, patent classification systems establish a taxonomy that includes multiple levels of detail, with highest-level classes and then multiple sub-classes within them (plus main groups/subgroups for the IPC). Manuals or guides are available explaining these taxonomies, including descriptions of the subject matter that each class/subclass is intended to cover. Classifications are assigned to individual patent documents by examiners, generally at an initial or pre-examination stage. Because the process of classification necessarily involves certain judgments, classifications can be prone to human error. Moreover, even in the best of circumstances, classifications are never perfect. For instance, at any given point in time classification systems may not recognize certain emerging technology areas in the sense that there may not be specific sub-classes in which to categorize such emerging technologies. Also, there may be subtle disclosures, such as things shown only in figures and/or left up to implication in the text, that may not be completely captured by a given patent office’s classifications. And yet, classifications can be a useful tool for patent searching. It is possible to combine classifications with particular keywords/terms as part of Boolean searches, which can be a powerful strategy to increase the precision of queries.
Forward and backward searching refers to searching references that are cited in the “references cited” section of a given relevant patent (backward searching) or searching for later patents in which the “references cited” section cites back to a given relevant patent (forward searching). The essence of forward and backward searching is that you begin with one or more patent documents that you have already determined to contain relevant subject matter and then you piggyback on prior searches that others have performed in relation to other patents, leveraging the past efforts of others to compile groupings of technologically-related references. In other words, forward and backward searching treats citations within and back to a given relevant patent as a kind of quasi-classification system. But forward and backward searching can never be the initial starting point for a search, because you must begin with at least one relevant patent—ideally the most relevant patent(s) you could find through other avenues. Yet forward and backward searching can sometimes be the most effective method for increasing search recall. The same principles can be applied to citations and bibliographies in non-patent literature.
Other available patent searching tools utilize natural language searching, semantic searching, machine learning, artificial intelligence (AI), or the like. Typically, such search tools utilize some type of proprietary algorithms to parse and execute search queries. With natural language, semantic, or AI searching, the general idea is often that a searcher inputs words in a narrative format—unlike formal Boolean search syntax—and the tool applies its algorithms to convert those inputs into one or more queries that are run against the database to produce a result set. Of note is that the use of proprietary algorithms mean that the search tool runs these searches through what can be called a “black box”—the searcher typically has no idea what happens inside that black box and thus no real sense of what might be omitted or excluded from the result set. Some evidence from the legal research context suggests that experienced attorneys do not trust “black box” search algorithms.[13] There are some tools, potentially most applicable to design patent searching (or trade dress searches), in which a searcher uploads an image file and the search tool utilizes image matching software to try to locate documents containing similar images. As of today, these patent searching tools are still “bleeding edge” technologies and there is generally a lack of independent and peer-reviewed studies to validate the effectiveness of AI (etc.) them. Vendors frequently make claims about studies they have done themselves, though it is difficult to place any trust in such studies used for marketing purposes when often there is no disclosure of the methodology employed and vendors have strong incentives to succumb to self-interest bias. Much of the available literature on the subject can be characterized as marketing “advertorials”. And for that matter, because AI-powered tools almost always rely on proprietary “black box” algorithms there is no way to know how a study involving one black box relates to another black box—or even if a study of a given search tool in the past still applies to that search tool, given that changes to that proprietary tool may occur within the black box without any way for a user or investigator to know. These concerns echo the reasons experienced attorneys do not trust black box legal research tools or with concerns over law enforcement usage of AI-powered facial-recognition tools or the like[14]—control is being surrendered over aspects of search queries to algorithms premised on undisclosed assumptions that may be important to outcomes. Perhaps as AI-powered patent searching tools become more sophisticated they will play a larger role. But as of today, a good rule of thumb is to rely principally on human-guided searches and utilize AI-type search tools only in a secondary sense, such as for initial “quick-start” or “drunk walk” search orientation efforts before running substantive queries, last-step search validation or auditing, or supplemental, almost “hail Mary pass” efforts to perhaps get lucky and find additional art otherwise missed through other avenues.
C. INID and Kind Codes
“INID” is an acronym for “Internationally agreed Numbers for the Identification of (bibliographic) Data” on patents.[15] Also referred to informally as “field codes”, these codes embody a system for the international harmonization of bibliographic data (or metadata) appearing on published patent documents, such as for the title (54), assignee name(s) (73), filing date (22), issue/grant date (45), etc.
INID Code
Data Field Content
(10)
Publication/Patent Number
(22)
Filing Date
(43)
Application Publication Date
(45)
Grant/Issue Date
(54)
Title
(71)
Applicant(s)
(73)
Assignee(s)
(86)
PCT Filing Details
Table of Selected INID “Field” Codes
These INID/field codes can be tremendously useful when fetching individual patents in another language. For example, either by referring to a table that identifies INID code numbers and the associate data content description, or simply referring to a sample patent in a known language, the location of similar data on a foreign-language patent document can be located. While machine translations of patent documents are now frequently available, machine translations of very old patent documents are not always available. And many machine translation tools may be unable to reliably parse PDFs of old patent documents, though it may be possible to perform limited machine translations of just particular text—such as within a given INID field—to ascertain some basic information about a given patent document.
Comparison of INID “Field” Codes Between Patents in Different Languages
Camera-Based Partial Machine Translation of Selected Patent INID “Field” Contents
“Kind codes” identify type of patent and generally appear as a letter or letter and number (e.g., “A1” or “B2”) immediately after the patent or publication number.[16] The USPTO only began printing kind codes on U.S. patent documents on January 2, 2001, so older U.S. patents lack a kind code. Some countries have different types of patents—like utility models—that do not exist in the USA. And systems for assigning numbers to patents has, historically, not been particularly harmonized internationally.
Perhaps most confusing to U.S. practitioners is the Japanese patent numbering system, which in the past has assigned the same numbers to different patents differentiated only by the kind code.
Another potentially confusing practice involves the treatment of old U.S. patents that were issued without any kind code on their face to which the “A” kind code (without a numerical digit) is retroactively applied. This is potentially confusing because WIPO kind codes “A1”, “A2”, and “A9” are currently used by the USPTO to designate published patent applications. In other words, the old granted patent “A” designation retroactively applied in searching databases can easily be confused with the new “A1”, “A2”, and “A9” designations that apply only to published applications and never to granted patents.
V. Metrics for Evaluating Searches
The key metrics for evaluating information retrieval effectiveness in the patent context (or other library science contexts) are “precision” and “recall”. Recall is the proportion (%) of all relevant documents retrieved in a given search query or overall search; recall is hypothetically expressed as:
Precision is the proportion (%) of relevant documents versus irrelevant documents retrieved in a given search query or overall search; precision is hypothetically expressed as:
Put yet another way, perhaps more informally, “recall” measures how completely relevant materials have been located while “precision” measures how much unwanted or useless material has been captured. Library science has shown that recall and precision are tradeoffs with any given search query.[17] That is, increasing recall generally decreases precision and vice-versa.
In the patent searching context, 100% recall is always desired but 100% recall is only a theoretical objective. There is no way to know, definitively, the universe of all relevant materials against which to compare a given query or overall search. After all, if you knew at the outset what all the relevant materials were, why would you bother conducting a search merely to confirm what you already know? And yet, if further searching returns additional relevant results than you can retroactively determine that a prior query or set of queries had less than 100% recall. The rub is that this aspect of ascertaining 100% recall is like the impossibility of “proving a negative”: no matter how much you have searched, you can never know for certain whether or not there is at least one additional relevant reference that you simply have not yet located. At best, certain protocols can be employed as proxies for 100% recall (e.g., searching X number of databases for Y number of hours, finding no more relevant results after a certain number of queries or period of time, etc.) but such proxies necessarily involve certain assumptions that can always be questioned.
Practically speaking, precision is about efficiency and reliability. Search results that include irrelevant materials can raise questions about the reliability of the search—did the searcher not understand the specific information being sought?—and can also waste time—both in terms of requiring more efforts by the searcher but also impeding later work by anyone else utilizing imprecise, cluttered search results for a legal analysis or to make business decisions.
Some patent searching databases assign “relevancy” scores to individual results in a given query. Such “relevancy” scores are generally determined by proprietary algorithms baked into the database’s software. Whether the judgments embodied in those algorithms suit a searcher’s purpose is hard to know. Most vendors do not make public the algorithms or weighting used to assign relevancy scores. Searchers can anecdotally attest to performing searches where the “silver bullet” prior art was assigned a low relevancy score by the database tool. Database “relevancy” scores are not meaningful as metrics for assessing search quality. Though they might still be useful in (theoretically) presenting voluminous query results in an order that is more helpful for review.
VI. Evidentiary Burdens, Privileges, and Disclosure Duties
A. Evidentiary Issues for NPL References and Public Use/On-Sale Evidence
District court proceedings where invalidity is alleged follow the Federal Rules of Evidence (FRE).[18] PTAB trials at the USPTO (PGRs, IPRs, Derivations) also generally follow the FRE.[19] Under the FRE, a document introduced as “prior art” must satisfy rules requiring authentication and prohibiting hearsay (unless an exception applies).[20] These evidentiary burdens are not a concern for U.S. patents and published patent applications, which as “public records” are self-authenticating (FRE 902) and fall in a hearsay exception (FRE 803(8)) to qualify them as prior art. In practical terms, authentication/hearsay objections to foreign patents and published patent applications are unlikely—and a party bringing such objections is just going to annoy the judge. Evidentiary issues surrounding domestic and foreign patents should really only arise in rare if not unheard-of situations where forgeries are being proffered. But evidentiary issues for NPL references, on-sale activities, and the like cannot be taken for granted.[21] For instance, the Federal Circuit has held that “corroboration is required of any witness whose testimony alone is asserted to invalidate a patent.”[22]
However, during ordinary examination and reexamination lower evidentiary standards apply to NPL references and compliance with the FRE (or similar PTAB trial procedures) is unnecessary.[23]
B. Qualifying a Non-Patent Literature (NPL) Reference as “Prior Art”
In order to qualify as “prior art”, an NPL reference must be established as a “printed publication” that was sufficiently generally “publicly accessible” before the critical date—and that must be done in accordance with the hearsay and authentication requirements discussed above for district court litigation and PTAB trials. “‘[P]ublic accessibility’ has been called the touchstone in determining whether a reference constitutes a ‘printed publication[.]’”[24] “A reference will be considered publicly accessible if it was disseminated or otherwise made available to the extent that persons interested and ordinarily skilled in the subject matter or art exercising reasonable diligence[] can locate it.”[25] “Whether a reference is publicly accessible is determined on a case-by-case basis based on the ‘facts and circumstances surrounding the reference’s disclosure to members of the public.’”[26] Limited distribution, even to those skilled in the art, may not amount to “publication” unless the material is otherwise so situated that “anyone who chooses may avail himself of the information it contains.”[27] While evidence of “indexing” can establish public accessibility, it is merely one among many ways to establish “printed publication” status.[28]
In the invalidity context, it cannot be assumed that a copyright date, printing date, Internet server upload date, or the like appearing on the face of the NPL reference will necessarily satisfy public availability evidentiary requirement. Courts and the PTAB have rejected such arguments in numerous cases.[29] But clear indications on or within an NPL reference evincing publication by an established publisher with traditional hallmarks of publication (ISBN, etc.) might be sufficient. Courts and the PTAB have occasionally found such evidence sufficient, particularly when dealing with very conventional publications like a (hard copy) book from a well-known publisher or an industry standard published by a well-known standards-setting organization.[30] Commonly, the publication of NPL materials is substantiated by testimony from a librarian who cataloged or indexed a book or magazine as of a particular date. In those situations, merely finding a particular disclosure is not enough to qualify the NPL reference as “prior art”—it may also be necessary to locate a witness to corroborate public accessibility.
Materials from Internet web sites constitute an important category of NPL references where hearsay concerns can be significant. Once again, the mere appearance of a date on the face of a web page (or in the URL, etc.) will not ordinarily be sufficient to establish the web page as a printed publication that qualifies as “prior art” before a critical date. It is possible to offer witness testimony to establish web page publication, just as with books, magazines, and the like. But one unique avenue for satisfying evidentiary burdens to qualify a web page as prior art is to utilize archival records from the Internet Archive’s “Wayback Machine” (archive.org) or its equivalent.[31]
Other ephemeral or temporarily displayed materials, such as posters, videos, or presentation slides temporarily displayed at trade shows or conferences, raise other unique issues regarding their status as printed publications that qualify as “prior art”.[32] But they may qualify as prior art under various circumstances.
Also remember that standards of proof differ depending on where a validity or unpatentability challenge is lodged. A preponderance of the evidence standard is applied at the USPTO whereas a clear and convincing evidence standard is applied in district courts. These different standards of proof can make a difference in whether or not available evidence establishes something as “prior art”. Some reported decisions are less than explicit about the standard of proof being applied, which may help make sense of decisions that otherwise might seem inconsistent.
C. Privileges and Their Limits
The attorney-client privilege and work-product protections may shield certain materials from discovery. Yet materials generated in connection with searches are not always privileged.
Attorney-client privilege only applies to communications actually sent, and only when seeking or providing legal advice.[33] Such communications must involve an attorney or someone acting under the supervision and control of an attorney; and just because a communication involves an attorney does not automatically mean it is privileged. Privilege law varies across district courts and circuits but some courts have held that the acts of counsel, the general topics of discussion, and the ultimate legal conclusions are not privileged. Moreover, communications involving in-house counsel are often scrutinized more closely and may be subject to a rebuttable presumption that they contain business rather than legal advice.[34] In general, anything that would have to be disclosed on a privilege log in litigation is not privileged.[35] For instance, a privilege log may need to identify patents by number, and documents found during patent infringement/prior art searches or reviewed by an expert witness might need to be identified or disclosed.[36]
Work product protection can preclude discovery of documents and tangible things that are “prepared in anticipation of litigation or for trial” by or for another party or its representative (including the other party’s attorney, consultant, or agent).[37] Work product protections can apply to the work product of non-attorneys but will not apply where business considerations predominate (regardless of the involvement of any attorney(s)).[38] Also, work product protection is not absolute, and can be overcome if the materials are otherwise discoverable and the party seeking discovery shows that it has substantial need for the materials to prepare its case and cannot, without undue hardship, obtain their substantial equivalent by other means.[39]
D. Duty of Disclosure
The duty of disclosure applicable to pending U.S. patent applications may necessitate some additional steps when relevant prior art is located in a search. “Each individual associated with the filing and prosecution of a patent application has a duty of candor and good faith in dealing with the [USPTO], which includes a duty to disclose . . . all information known to that individual to be material to patentability . . . .”[40] Deliberately withholding prior art material to patentability can render any resulting patent unenforceable.[41] Anyone substantively involved[42] with pending U.S. patent application(s) who receives search results on related subject matter should consider the need to submit search results on an information disclosure statement (IDS).
VII. Considerations for USPTO Post Grant Proceedings
Strategic and legal considerations regarding the type of post-grant challenge that might be leveled against a given patent will vary depending upon the available prior art. For that reason, it is usually desirable to locate prior art, or at least most of it, before deciding which type of post-grant proceeding will be sought. For example, certain types of post-grant proceedings can only be based on patents and printed publications. Moreover, the thresholds for institution of different types of proceedings vary;[43] though one constant is that all USPTO post-grant proceedings are based on a preponderance of the evidence standard for patentability while district court actions are based on the higher clear and convincing evidence standard for invalidity. Lastly, IPR institutions are on an all-or-nothing basis.[44]
PTAB trials involve estoppel that bars any further challenge based on any ground the petitioner “raised or reasonably could have raised” in a prior proceeding.[45] This amounts to a “use it or lose it” (or “cite it or forgetaboutit”) opportunity to present prior art in a PTAB trial petition for institution, and requires that essentially all prior art searching be completed before the petition is filed—and therefore, practically speaking, before a petition can be prepared by legal counsel. The PTAB and some district courts have interpreted and applied the “raised or reasonably could have raised” standard by asking whether a skilled searcher conducting a diligent search reasonably could have been expected to discover the prior art reference in question.[46] The PTAB has applied this standard in a rather strict and formalistic way, showing no sympathy if locating a patent document would have required “brute force” manual review of tens or hundreds of thousands of patents not in any apparently relevant class/subclass.[47] Courts have also considered whether particular prior art, such as a physical product that is not a “printed publication” but was potentialyl was on sale or in public use, reasonably could have been raised in a PTAB trial.[48]
On the other hand, estoppel does not arise from ex parte reexamination. Though collateral estoppel (issue preclusion) from prior litigation can still apply to reexams.[49] Additionally, it is more difficult to sustain the unchanging clear and convincing evidence burden for subsequent invalidity challenges in district court when the USPTO already considered the same art.[50]
VIII. Considerations for Design Patents
For design searching, “brute force” manual review of all designs in relevant classifications is recommended. A major reason is that design patents have so little text that keyword searching is frequently unreliable. There is so little text that explanatory statements that normally appear in utility patents to provide an enabling disclosure for functional features is absent in design patents focused on ornamentation. And what little text there is in design patents might use words that are not especially helpful or reliable for purposes of a keyword search. Though initial keyword searching can still be helpful when seeking to identify relevant Locarno classifications. Another tip is to be sure to check for alternate embodiments that are not depicted in a representative figure on the front page of the design patent (or shown in representative thumbnail views by search tool databases). Another point to consider for design patents is that some subject matter areas may have relatively few prior art design patents, even in areas where commercial products have been sold and publicly used for decades. In such situations it may be necessary to investigate non-patent prior art in the form of evidence of on-sale activities, etc. Such investigations may call for a substantially different approach and timeline. Actually, such investigations may require considerable effort to locate and authenticate suitable evidence including witnesses/declarants.
Another challenge with design patent searching is that the Federal Circuit looks to the perspective of the ordinary designer (rather than the ordinary observer) for obviousness analyses and applies a two-part Durling test for obviousness.[51]
Somewhat unique to design patents is the opportunity to present prior art for a three-way comparison between images of the asserted patent, the prior art, and the accused product in “close” cases.[52] The burden is on the accused infringer to bring forward evidence of the closest prior art for a three-way comparison.[53]
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
[2] E.g., Digeo, Inc. v. Audible, Inc., 505 F.3d 1362, 1369-70 (Fed. Cir. 2007) (case not exceptional [frivolous] because defendant did not establish plaintiff knew or should have known it lacked legal title due to alleged forgeries); Q-Pharma, Inc. v. Andrew Jergens Co., 360 F.3d 1295, 1303 (Fed. Cir. 2004) (reasonable belief in presumption of validity made suit nonfrivolous under Rule 11).
[6] There may be rare situations in which relevant prior art is already known without conducting an invalidity search, though even then a search to locate additional prior art may have value.
[21] Cf. Wi-LAN Inc. v. Sharp Elecs. Corp., 992 F.3d 1366 (Fed. Cir. 2021) (proffered evidence of infringement inadmissible at summary judgment for lack of suitable authentication; 3d Circuit law applied).
[23] E.g., MPEP § 2128 (date on a document can establish its publication for examination purposes unless applicant challenges it); Ex parte Grillo-López, Appeal No. 2018-006082 at *2-3 (PTAB, Jan. 31, 2020) (precedential) (lower examination standards vs. higher IPR standards to establish publication).
[24] In re Hall, 781 F.2d 897, 899 (Fed. Cir. 1986).
[26] In re Lister, 583 F.3d 1307, 1311 (Fed. Cir. 2009) (quoting In re Klopfenstein, 380 F.3d 1345, 1350 (Fed. Cir. 2004)); see also Blue Calypso, LLC v. Groupon, Inc., 815 F.3d 1331, 1348 (Fed. Cir. 2016) (“Whether a reference qualifies as a printed publication is a legal conclusion based on underlying factual determinations.”).
[27] In re Bayer, 568 F.2d 1357, 1360, 1362 (CCPA 1978).
[28] E.g., In re Lister, 583 F.3d at 1312 (“neither cataloging nor indexing is a necessary condition for a reference to be publicly accessible.”).
[32] See, e.g., Medtronic, 891 F.3d at 1379-83; Initiative for Medics., Access & Knowledge (I-MAK), Inc. v. Gilead Pharmasset LLC, IPR2018-00123, Paper 7 at *8-11 (PTAB, June 13, 2018); In re Klopfenstein, 380 F.3d at 1347-50; Ecolochem, Inc. v. S. Cal. Edison Co., 227 F.3d 1361, 1369-70 (Fed. Cir. 2000).
[38] E.g., Sioux Steel Co. v. Prairie Land Millwright Servs., Inc., No. 1:16-cv-02212 (N.D. Ill., May 19, 2021) (factual information in technical drawings related to attempts to design around patent discoverable, but counsel’s mental impressions and opinions about those efforts and legal advice sought or received not discoverable); In re Google Inc., 462 F. App’x 975, 976-79 (Fed. Cir. 2012) (nonprecedential) (email captioned “Attorney Work Product” expressing need for license was a technical/business investigation not protected work product, nor attorney-client privileged); Takeda Chem. Inds., Ltd. v. Alphapharm Pty., Ltd., No. 04-cv-1966, 2005 WL 1678001 (S.D.N.Y., July 19, 2005) (routine patent searches in ordinary course of business, irrespective of litigation, not protected work product).
[46] Wasica Finance GmbH v. Schrader Int’l, 432 F. Supp. 3d 448, 453 (D. Del. 2020); IBM Corp. v. Intellectual Ventures II LLC, No. IPR2014-01465, Paper 32 at 5 (PTAB, Nov. 6, 2015).
[47] Valve Corp. v. Ironburg Inventions Ltd., IPR2017-00137, Paper 43 (PTAB, Jan. 25, 2018).
