Patents Q&A

What Is a Restriction Requirement?

The Basics of a Restriction Requirement

Patent examiners may issue a restriction requirement against a pending patent application. If two or more independent and distinct inventions are claimed in one patent application, the USPTO may require the application to be restricted to one of the inventions. A conventional restriction requirement means the examiner believes there are multiple independent or distinct inventions being claimed. The examiner will identify the different inventions by groups of claims. The applicant must then pick one claimed invention to be substantively examined for patentability. That is called making an election.

Every requirement to restrict has two aspects: (A) the reasons why each invention as claimed is either independent or distinct from the other(s); and (B) the reasons why there would be a serious burden on the examiner if restriction was not required. The second aspect refers to the burden to search for prior art and evaluate the claimed invention against the search results.

A restriction requirement is not considered to be an office action on the merits. That is, it is not considered to be a substantive determination as to patentability. Restriction requirements normally arise before a first office action on the merits. However, it is also possible for restriction to arise after a first action on the merits, such as where an applicant later adds or amends claims to recite an independent or distinct invention from what was originally presented.

Examiners will frequently call the applicant’s counsel of record by phone to present a restriction requirement. This use of oral elections is meant to speed up examination and avoid the need to send written documents back-and-forth.

Election of species requirements are related to but distinct from restriction requirements among claims. Election requirements for disclosed species are discussed in detail elsewhere.

Determining Whether Claims Are Independent or Distinct

For purposes of restriction practice, claims are “independent” if there is no disclosed relationship between the inventions, that is, they are unconnected in design, operation, and effect. This type of restriction is straightforward. It does not come up that often. An example of independent inventions is an application that discloses and claims an invention for a dental prosthetic device and another, unrelated invention for a chemical compound for polishing shoes.

Restrictions between related but “distinct” inventions are more common. These restrictions are closely tied to prohibitions against double patenting. The precise requirements for a proper distinctness restriction will depend on the types of claims involved. A lower standard applies to restrict out inventions in different statutory categories—generally referring to the difference between apparatus and method/process claims. However, for applications with so-called combination and subcombination claims (e.g., claims to an overall device and to a subassembly usable in it), or with claims to related products or related processes (i.e., claims in the same statutory category), a higher standard is applied. Further, even when claims are distinct, the examiner must also show that examining those claims together would pose a serious burden.

For example, a device disclosed in a patent application might have a unique mechanical actuator, a special chemical composition for a coating on the actuator, and a unique electronic controller. If each of those aspects is set forth in separate and distinct independent claims, it is understandable that a single examiner may not have expertise in mechanical, chemical, and electrical technologies to examiner each of them together. That is true even when each of the distinct invention is related in the sense of being usable together in the same device. But claiming distinct inventions in a way that means they could be used separately, without the use of the other inventions, presents the possibility of a restriction.

After a Restriction Requirement Is Issued

Following a restriction requirement, the applicant is required to elect one group of claim(s) for examination. Unelected (or nonelected) claims will be withdrawn and will not be substantively examined. Importantly, an applicant will generally be prohibited from later adding claims to an invention independent or distinct from the elected claims. There is generally no opportunity to change your election later on. Although “rejoinder” may permit previously unelected claims to be allowed if they depend from or otherwise require all the limitations of an allowable claim.

Restriction requirements can be important for later determinations. Going forward, the examiner is bound by the restriction. For instance, an examiner cannot later claim that certain claim limitations have no patentable significance when a prior restriction requirement insisted otherwise. A restriction requirement also means that double patenting is inapplicable. This means an applicant can file a new divisional application to unelected claims without receiving a double patenting rejection, avoiding the need for a terminal disclaimer. This might result in patent term adjustment that extends the expiration of the divisional patent beyond that of the earlier (parent) application.

Considerations for how to respond to a restriction of claims in a patent application are discussed here.

Why Are Restriction Requirements Made?

Because applicants can prepare patent applications any way they choose, it is possible a given application could include multiple inventions. The existence of U.S. restriction practice is the other side of the coin to the availability of divisional applications. A divisional application allows an applicant to file a further patent application to another disclosed invention. Restriction practice is meant to prevent applicants from imposing unreasonable examination demands on patent examiners. Although if an examiner chooses not to restrict claims in a given application that has no effect on validity of a resultant patent.

Examiners have considerable discretion about issuing restriction requirements. There is considerable variation in how restriction practice is utilized by different examiners, and also between different art units or technology centers at the USPTO.

Applicants are sometimes frustrated by restriction requirements. They can have the appearance of an examiner trying to avoid work or to game the “count” system, which the USPTO uses internally to track examiner productivity, by forcing the applicant to file a divisional application. At times, rationales given for restrictions can seem unconvincing or circular. Also, while the USPTO’s guidance (see, e.g., MPEP 801.02) states that restriction is permitted when there are either independent or distinct inventions claimed, some argue that the patent statutes (and corresponding regulations) should be interpreted to permit restriction only among claimed inventions that are both independent and distinct. Others complain that the USPTO has overstepped its authority by allowing an alleged serious “examination burden” to justify restriction without showing a serious “search burden”. On the other hand, applicants seeking to avoid official fees normally associated with filing separate patent applications for independent and distinct inventions are rightfully subject to restriction requirements.

PCT National Phase Entry Applications

Regular restriction practice does not apply to PCT national phase entry applications. Instead, a unity of invention standard governs, which requires having a common or corresponding special technical feature that defines a contribution over the prior art. However, U.S. examiners can still issue requirements to elect a particular invention in national phase applications and withdraw unelected claims and the procedures are similar. Applicants must still make elections and rejoinder of withdrawn claims is still possible. This means that the ultimate effects are similar though the terminology differs somewhat. If anything, there is slightly greater leeway for applicants to amend the claims to keep them together under the unity of invention standard.

It is important to note that the USPTO can make an independent determination of unity of invention. Prior indications by the international search authority or international preliminary examining authority in the international phase of a PCT application are not binding in the national phase. That means that even if a prior PCT written opinion indicated that claims posses unity of invention, the U.S. examiner could disagree and still issue a unity of invention restriction in the national phase.

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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.