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"Restriction Requirements" Series, Part 1: Considering Restrictions When Developing a Claim Filing Strategy

US Pat and YouWelcome to the blog’s first post in a series about restriction requirements! This series will explore nuances in restriction requirement law and provide strategies for most effectively handling restriction requirements, both before and after they arise during prosecution of a U.S. patent. This first post focuses on strategies for developing an initial claim filing strategy that advantageously takes possible future restriction requirements into account.

Let’s begin with a brief overview of U.S. restriction requirements. Per 35 U.S.C. § 121, a restriction requirement generally requires an applicant to elect for prosecution only one of two or more independent and distinct inventions presented in a single application. Patent rules 37 CFR §§ 1.141-1.146 are issued under 35 U.S.C. § 121 and also govern U.S. restriction practice. Per these legal requirements, a restriction requirement identifies two or more Groups/Genus, two or more Species, and/or two or more Sub-species that an applicant must choose between for substantive examination. Examiners typically require restriction between inventions before the issuance of a first Office Action on the merits, but Examiners can require restriction at any time during prosecution as a standalone action or, after the first Office Action, as part of an Office Action.

Given the Examiner’s wide discretion in both the timing and content of restriction requirements, it is important for applicants to always be aware of the possibility of receiving a restriction requirement because restrictions can suddenly limit the type or scope of claims that can be pursued in an application, absent the new filing of a divisional or continuation application.

Awareness of restriction requirements best begins before an application is even filed – during preparation of the application’s initial claims.

It can sometimes be beneficial to purposely file claims that an Examiner may consider to be directed to independent and distinct inventions. In other words, filing claims that lend themselves to restriction requirements can help encourage the issuance of a restriction requirement. Why would you want to invite a restriction requirement as part of an initial claim filing strategy?

  • Preserve Patent Term: Restriction requirements open the door under 35 U.S.C. § 121 for the filing of divisional applications pursuing unelected claims. Double patenting rejections cannot be made in a divisional application over the parent application including the restriction requirement that resulted in the filing of the divisional application (see MPEP § 804, 804.01). Terminal disclaimers to overcome double patenting rejections will therefore not be filed in a divisional application over its parent application that included the restriction requirement, thereby helping to maximize the patent term of the divisional application. Even if more than twenty claims and/or more than three independent claims are filed with the expectation of possibly receiving a restriction requirement, the excess claim fees paid at filing can be well compensated for by patent term savings.
  • Preserve Economic Value: At the time of filing, the economic importance of various embodiments disclosed in the application may not yet be known. Similarly, the embodiments that seem most economically important at the time of filing may not be the embodiments that are most economically important years down the line when examination of the application begins at the U.S. Patent and Trademark Office. Initially filing claims that cover all embodiments with any possible economic value can help ensure that the most valuable claims can be pursued without being blocked by an Examiner’s requirement for restriction (and thus requiring the filing of – and payment for – a divisional or continuation application). Leaving your options open with a varied claim set upon filing can thus help you to get a more valuable patent at the outset.
  • Preempt Election By Original Presentation: 37 CFR 1.145 generally explains the doctrine of election by original presentation by providing that “[i]f, after an office action on an application, the applicant presents claims directed to an invention distinct from and independent of the invention previously claimed, the applicant will be required to restrict the claims to the invention previously claimed if the amendment is entered.” This doctrine will be explored in detail in a future blog post in this series. For purposes of preparing initial claims, it is important to remember this doctrine and to consider including specific claims to different embodiments in order to avoid the surprise of being restricted from pursuing a particular invention not specifically recited in the originally examined claims.

Of course, you cannot fully predict when or if an Examiner will require restriction, but an applicant not being afraid to receive a restriction requirement can pay dividends down the road.

Also remember that jurisdictions outside the U.S. generally do not have the same restriction rules (often called “unity” rules overseas) as the U.S. If a U.S. application serves as the basis for a foreign application, claims that may not be examined in the U.S. for restriction reasons may be examined elsewhere. Thus, writing as robust and as complete an initial claim set as possible can help a foreign patent have expansive coverage even if the corresponding U.S. patent is more limited in scope because of restrictions issued during U.S. prosecution. Similarly, if a foreign application subject to more strict unity rules than the U.S.’s restriction rules serves as the basis for a U.S. application, consider whether the claims should be amended in the U.S. to take advantage of the more expansive examination possibilities in the U.S.

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Christina Sperry is a Mintz patent attorney who drafts and prosecutes patents for clients in the electrical, mechanical, and electro-mechanical fields. She represents companies and academic institutions in the medical technology field and helps protect patent innovations for medical and surgical devices.