Responding to Nonstatutory Double Patenting Rejections: A Practitioner’s Perspective

By Russell S. Timm and JD Wooten

Published in Landslide Vol. 11 No. 4, ©2019 by the American Bar Association. Reproduced with permission. All rights reserved. This information or any portion thereof may not be copied or disseminated in any form or by any means or stored in an electronic database or retrieval system without the express written consent of the American Bar Association.

Given the increasing scrutiny of courts and patent examiners, nonstatutory double patenting rejections can be fraught with both challenges and risks. Although almost all obviousness-type, nonstatutory double patenting rejections can be based on both anticipation and obviousness rationales.1 Overcoming the challenges and minimizing the risks in order to achieve the best outcome for your client can be made easier by approaching a response to such a rejection in five sequential steps.

Initially, you should take into account any preliminary considerations. Recognize the general nature of the rejection, consider whether pre-America Invents Act (AIA) or AIA law applies, and identify the parties associated with the applications or patents involved in the rejection. Once that is done, think about obviating the rejection. If you do not believe that the rejection can be obviated, consider requesting that the rejection be held in abeyance, notwithstanding that (for reasons discussed hereafter) there are some very limited circumstances in which such a request is proper. If a rejection cannot be obviated or held in abeyance, the next step is to contemplate arguing the rejection on the merits. Finally, sometimes the last resort (i.e., filing a terminal disclaimer) may be the best resort.

Preliminary Considerations

Preliminary considerations encompass answering questions that are pertinent to one or more subsequent steps of formulating a response to the rejection (or at least having the discussion with your client):

What is the relationship? In many, but not all, cases, there is a legal relationship between the rejected application and the reference application or patent, and up until recently the reference application or patent inevitably had the same or earlier effective priority date. Post-Gilead, some examiners will issue what might be best characterized as an “inverted” rejection, i.e., a rejection in which the reference application or patent has an effective priority date that may be months or years later.2 If an “inverted” rejection is at least prima facie proper (i.e., cannot be obviated), then it is for all intents and purposes impossible to argue on the merits given that the reference is almost certainly directed to some improvement of the invention being claimed in your application.

Which law applies? As one naturally expects, your application and reference application or patent are governed by either pre-AIA or AIA provisions of 35 U.S.C. Fortunately, the impact of the AIA on these types of rejections is nowhere near as significant as it is on novelty and obviousness rejections under 35 U.S.C. §§ 102 and 103, respectively. The good news is that the ways to obviate the rejection or overcome the rejection on the merits are essentially the same, irrespective of which law applies. The bad news is that the ways to obviate the rejection or overcome the rejection on the merits are equally as difficult, irrespective of which law applies. The law will, however, impact whether or not you can readily file a terminal disclaimer under 37 C.F.R. § 1.321(d) based on the existence of a joint research agreement.

Who is involved? It should come as no surprise to many readers that in many cases the application under rejection and the reference application or patent share at least one common owner or assignee (presumably your client). While this forecloses one route of obviating the rejection, it does at least provide an indication that at least one type of terminal disclaimer (i.e., one based on common ownership) might be readily available to overcome the rejection if all else fails.

However, in order to file a terminal disclaimer under 37 C.F.R. § 1.321(c), you should confirm that that ownership interests in both the rejected application and the reference application or patent are identical.3 If your client is the sole owner or assignee, then establishing common ownership should be straightforward. If multiple parties are involved, then identifying ownership interests may be a bit more complicated.

When a nonstatutory double patenting rejection implicates multiple parties, initially the practitioner should identify whether all parties have an ownership interest in both the rejected application and the reference application or patent. This is the hallmark of common ownership as far as the U.S. Patent and Trademark Office (USPTO) is concerned, and the Manual of Patent Examining Procedure (MPEP) has many examples illustrating when common ownership does and does not exist.4

A rejection implicating multiple parties also brings into question whether or not a joint research agreement is in effect between the parties concerned. If so, a terminal disclaimer under 37 C.F.R. § 1.321(d) may be an option to consider if all other options for response are exhausted. As mentioned previously, which law applies to your application does influence terminal disclaimers, so you should have a discussion with your client about the particulars of the joint research agreement (if one exists).

When multiple parties are involved, arriving at a response that will make all parties happy may also be harder to achieve. This is particularly true if a rejection is not based on the existence of a shared owner or assignee, but rather a common inventor.5 If your client has a formal (or at least working) relationship with the other party or parties, then your job may be somewhat easier. However, if you have to go the disclaimer route, you might want to have a conversation with your client about who controls the fate of any disclaimed patents in order to avoid any unpleasant surprises later on.6

Finally, if the reference serving as the basis of the rejection is an application rather than a patent, it is definitely advantageous if you have prosecutorial control of both applications and if the same examiner is responsible for both applications. You will simply have more options for responding to the rejection and fewer people to deal with in doing so.

Obviating the Rejection

Obviating a nonstatutory double patenting rejection boils down to whether or not you can demonstrate to an examiner’s satisfaction that the rejection is prima facie improper. In order for an examiner to issue a proper rejection, one or more “touchstones” or conditions precedent to the rejection must be present. The application and the reference application or patent must have at least one common inventor, applicant, owner, or assignee. Alternatively, the application and the reference application or patent may be non-commonly owned or assigned but subject to a joint research agreement. If none of these touchstones exists, then the rejection is prima facie improper.

Another easy way out of a rejection is if the examiner has failed to recognize that your application is a divisional of the reference application or patent and is thus entitled to the “safe harbor” under 35 U.S.C. § 121. A patent issuing on an application subject to a restriction requirement, or on an application filed as a result of such a requirement, must not be used as a reference either by the USPTO or the courts against a divisional application or against the original application or any patent issued on either of them, if the divisional application is filed before the issuance of the patent on the other application. Of course, utilizing the safe harbor requires that the claims of the putative divisional are consonant with the restriction requirement.7

While an unrecognized safe harbor very rarely comes up, it can come up in one of three foreseeable instances. First, a divisional application may be errantly filed as a continuation. While correcting this error is possible, doing so may raise flags within the USPTO. One should expect that quality assurance specialists will investigate such a request in order to ascertain whether the correction amounts to a form of impermissible recapture. Second, the examiner of the earlier-filed application or issued patent may be different than your presently rejected application. This can happen when examiners leave the USPTO, are promoted to different positions, or are assigned a different caseload. Third, and finally, the examiner may dispute the characterization of the application as a divisional and/or be of the opinion that the divisional is not entitled to the safe harbor under 35 U.S.C. § 121.8

Yet another way to obviate a nonstatutory double patenting rejection involves the relationship between the reference and the rejected application. If the reference is another pending application, then the rejection is provisional. Accordingly, you might consider amending or canceling claims to at least temporarily address the rejection. If you are prosecuting both applications, then you have even more flexibility when it comes to amending or canceling claims.

Furthermore, if the rejected application is the earlier-filed of the two applications and there are no other rejections remaining, the examiner should withdraw the rejection in the application having the earliest effective U.S. filing date and permit that application to issue as a patent. Keep in mind that priority or benefit claims under 35 U.S.C. § 119(a) and (e) are not taken into account in determining which application has the earliest effective priority date.9

There are also ways to obviate a nonstatutory double patenting rejection for more substantive reasons. For example, the examiner may be using the specification of the reference application improperly in making the rejection. While use of the reference specification is not completely off limits, there are restrictions on how the examiner may use the reference specification. Having said that, there are several cases that have the metes and bounds of these restrictions.10

In making the rejection, the examiner may also have used a one-way determination of (patentable) distinctness when he or she should have used a two-way determination of distinctness. The examiner should apply a two-way test when an applicant could not have filed the claims at issue in a single application and the USPTO is solely responsible for any delays in examination. Unfortunately, this will not provide a solution to an “inverted” Gilead-type nonstatutory double patenting rejection described previously, because although you may be able to successfully argue that the reference claims could not have been presented earlier, the USPTO is not responsible for the delay.

As a final note, in some very rare instances, an examiner may cite a later-filed unpublished continuation application as the basis of a nonstatutory double patenting rejection. This seemingly violates 35 U.S.C. § 122(a), which provides that patent applications are to be kept in confidence by the USPTO and no information is to be disclosed without authority of the applicant or owner unless necessary to carry out the provisions of an Act of Congress or in such special circumstances as may be determined by the Director. The reason that this very rarely occurs is that pursuant to 35 U.S.C. § 122(b), an application should promptly publish after the expiration of a period of 18 months from its earliest priority date. Thus, under almost all circumstances, the fact that the continuation application has not published is not reflective of 35 U.S.C. § 122(a), but rather USPTO delay. While this may or may not qualify as a “special circumstance,” relying on 35 U.S.C. § 122(a) is not very likely to be successful, and if it is, it will only delay the inevitable.11

Requesting That the Rejection Be Held in Abeyance

If attempting to obviate the rejection seems untenable, you might consider requesting that the examiner withhold the rejection in abeyance until the claims are otherwise in condition for allowance. Historically, this request has been routinely granted by examiners as it promotes prosecutorial efficiency. A patent applicant may focus on addressing any other rejections first, and once those rejections have been overcome by amendments or arguments, the examiner can reevaluate whether or not the nonstatutory double patenting rejection should be maintained.

Unfortunately, such a request no longer constitutes a proper response to the rejection. It is certainly possible that some within the USPTO never considered such a request to constitute a proper response, but the most recent revision to MPEP § 804 now makes clear that “[s]uch a filing should not be held in abeyance” because only objections or requirements as to the form of the claims may be held in abeyance.12 A response to the rejection is required even if the nonstatutory double patenting rejection is provisional in nature.

A proper response to a nonstatutory double patenting rejection constitutes a “complete reply” to the rejection, which entails one of two things according to the USPTO: you must demonstrate that your claims are patentably distinct from the reference claims, or you must file a terminal disclaimer. The former is technically not true, however, as merely arguing the rejection on the merits constitutes a “complete reply” irrespective of whether or not the examiner concurs with your position that your claims are patentably distinct from the reference claims.

Notwithstanding the USPTO’s position, some examiners may use their “discretion” and still grant a request to withhold a rejection in abeyance because it promotes prosecutorial efficiency. However, we would caution the reader that a question arises as to whether such a request constitutes a complete reply such that you are submitting a bona fide response to an office action. We would suggest that you do not want to find out to the contrary near or after the expiration of a six-month statutory period, because it could cost your client (or you) significant extension of time fees and require a costly petition to revive an unintentionally abandoned application.13 If you are adamant about trying it anyway, then we suggest concurrently filing a petition requesting suspension of the rules,14 but you should not expect that the petitions branch is going to view this issue the same way an examiner might.

Arguing the Rejection of the Merits

The next step is deciding whether the rejection can—or should—be argued on its merits. Doing so certainly has appreciable risks, given that you are going to have to submit remarks on the record characterizing not only your client’s present invention, but in most circumstances another one of its inventions as well.

The legal framework that governs arguing a nonstatutory double patenting rejection on the merits is set forth in Graham v. John Deere Co. of Kansas City.15 Given that the approach to arguing such a rejection is nearly identical to arguing an obviousness rejection under 35 U.S.C. § 103, addressing the obviousness rationales set forth in KSR International Co. v. Teleflex Inc.16 is also warranted in our view. Although MPEP § 804 does not mention KSR in this context, the Federal Circuit has discussed KSR in connection with a nonstatutory double patenting rejection.17 Performing a KSR analysis may also help insulate the application from a double patenting challenge in litigation should the application ultimately issue as a patent.

Successfully overcoming a nonstatutory double patenting rejection by way of argument can be quite difficult, and it often comes down to the “story” a practitioner conveys. Generally, such a “story” advances arguments that are data-driven and attempt to substantiate a lack of predictability in the art and/or a lack of a reasonable expectation of success.18

Filing a Terminal Disclaimer: Preliminary Considerations

Once all other options have been exhausted, the final option is to file a terminal disclaimer.19 While you may have options insofar as a terminal disclaimer may be filed on the basis of common ownership or the existence of a joint research agreement, there are some points to keep in mind.

All terminal disclaimers must be signed by the applicant and/or assignee or attorney or agent of record.20 A registered practitioner acting in a representative capacity under 37 C.F.R. § 1.34 is not permitted to sign a terminal disclaimer. This is likely to arise if a power of attorney has not been filed with and accepted by the USPTO prior to the filing of the terminal disclaimer.

All terminal disclaimers must specify the portion of the term of the patent being disclaimed21 and the present extent of the applicant’s ownership interest in the patent to be granted.22 Terminal disclaimers are also not free of charge.23

Although the filing of a terminal disclaimer is not an admission of the propriety of the rejection,24 a recent Federal Circuit case brings this particular premise into question.25

A terminal disclaimer can address a nonstatutory double patenting rejection, but cannot be used to overcome a statutory-type double patenting rejection or a rejection based on 35 U.S.C. § 101. You also cannot obviate a nonstatutory double patenting rejection by disclaiming the claims of an earlier patent.26

A terminal disclaimer may be withdrawn before issuance of the patent by filing a petition under 37 C.F.R. § 1.182 requesting withdrawal of the recorded terminal disclaimer. However, a terminal disclaimer may not be withdrawn after issuance of the patent. Furthermore, the intentional filing of a terminal disclaimer to overcome a nonstatutory double patenting rejection is not correctible through reissue under 35 U.S.C. § 251 or a certificate of correction under 35 U.S.C. § 255.27

Previously, if the practitioner inadvertently transposed numbers in a terminal disclaimer, the USPTO would accept a petition under 37 C.F.R. § 1.182 to withdraw the erroneous terminal disclaimer and replace it with a corrected terminal disclaimer. This is no longer true. Now, a request to replace or remove a previously recorded terminal disclaimer will not be addressed on the merits. Instead, the applicant may file a paper explaining the error(s) and requesting that the explanation be included in the file history and its request acknowledged.28

If a terminal disclaimer is to be filed on the basis of common ownership, then (as stated previously) the ownership interests in the application and the reference application or patent must be identical.29 You should also keep in mind that two or more patents that are subject to a terminal disclaimer under 37 C.F.R. § 1.321(c) are only enforceable as long as they are commonly owned. In fact, any terminal disclaimer submitted under 37 C.F.R. § 1.321(c) must expressly state as much.30

If a terminal disclaimer is to be filed on the basis of the existence of a joint research agreement, then obviously a joint research agreement must be in place between all the relevant parties. Furthermore, the claimed invention must be made as a result of activities undertaken within the scope of the joint research agreement,31 and the joint research agreement must have been in effect either on or before the date the claimed invention was made (in a pre-AIA application) or on or before the effective filing date of the claimed invention (in an AIA case). To complicate matters further, the reference application or patent must be able to be disqualified as prior art under either pre-AIA 35 U.S.C § 102(e), (f), or (g) or AIA 35 U.S.C § 102(a)(2).32 If either of these conditions cannot be met, then you might consider submitting the terminal disclaimer under 37 C.F.R. § 1.321(d) along with a petition requesting suspension of the rules under 37 C.F.R. § 1.183.

If a terminal disclaimer based on the existence of a joint research agreement is accepted, then you should keep in mind that the application must disclose or be amended to disclose the names of the parties to the joint research agreement, and that two or more patents that are subject to a terminal disclaimer under 37 C.F.R. § 1.321(d) are only enforceable as long as they are commonly enforced. The common enforcement provision33 is important to keep in mind because the USPTO does not presently have form-fillable or electronic § 1.321(d) disclaimers.34 Furthermore, the ramifications of a common enforcement provision should also be considered in instances where a foreseeable infringer might not infringe the claims of every patent subject to the disclaimer.


As illustrated herein, there are many ways to respond to nonstatutory double patenting rejections. Considering the various options and their short-term and long-term ramifications in a step-wise manner, a patent practitioner will almost invariably achieve the best possible result for the client.


1. See U.S. Patent & Trademark Office, Manual of Patent Examining Procedure (MPEP) § 804 (9th ed. Rev. 08.2017, Jan. 2018). Admittedly, it is our view that a double patenting rejection that is based on alleged anticipation but is not of the statutory type should have fairly unique facts underlying the basis of the rejection.

2. Gilead Scis., Inc. v. Natco Pharma Ltd., 753 F.3d 1208, 1214 (Fed. Cir. 2014) (holding that “a later-issued patent can serve as [an obviousness-type] double patenting reference for an earlier-issued patent if the later one expires first”).

3. The USPTO is not going to conduct an investigation into the propriety of the filing of a terminal disclaimer absent obvious discrepancies.

4. See MPEP, supra note 1, § 706.02.

5. See, e.g., In re Hubbell, 709 F.3d 1140, 1145 (Fed. Cir. 2013) (declining to recognize an equitable right to file a terminal disclaimer to overcome an obvious-type double patenting rejection where “an application and a conflicting patent share common inventors but do not have identical inventive entities, were never commonly owned, and are not subject to a joint research agreement”).

6. STC.UNM v. Intel Corp., 754 F.3d 940, 946 (Fed. Cir. 2014) (holding that “the right of a patent co-owner to impede an infringement suit brought by another co-owner is a substantive right that trumps the procedural rule for involuntary joinder,” and that a co-owner may not bring suit against a third party when another co-owner refuses to join the litigation).

7. See 35 U.S.C. § 121.

8. Boehringer Ingelheim Int’l GmbH v. Barr Labs., Inc., 592 F.3d 1340, 1352 (Fed. Cir. 2010).

9. MPEP, supra note 1, § 804(I)(B)(1)(b)(i).

10. See, e.g., AbbVie Inc. v. Mathilda & Terence Kennedy Inst. of Rheumatology Tr., 764 F.3d 1366 (Fed. Cir. 2014); Eli Lilly & Co. v. Teva Parenteral Meds., Inc., 689 F.3d 1368 (Fed. Cir. 2012); Sun Pharm. Indus., Ltd. v. Eli Lilly & Co., 611 F.3d 1381 (Fed. Cir. 2010); Pfizer, Inc. v. Teva Pharm. USA, Inc., 518 F.3d 1353 (Fed. Cir. 2008); Geneva Pharm., Inc. v. GlaxoSmithKline PLC, 349 F.3d 1373 (Fed. Cir. 2003); In re Vogel, 422 F.2d 438 (C.C.P.A. 1970); In re Baird, 348 F.2d 974 (C.C.P.A. 1965); In re Greenlee, 222 F.2d 739 (C.C.P.A. 1955).

11. Provided the examiner accepts your argument, the examiner is likely to just wait until the continuation application actually publishes and then reissue the rejection.

12. 37 C.F.R. § 1.111.

13. Id. § 1.137(b).

14. Id. § 1.183.

15. 383 U.S. 1 (1966).

16. 550 U.S. 398 (2007).

17. Otsuka Pharm. Co., Ltd. v. Sandoz, Inc., 678 F.3d 1280 (Fed. Cir. 2012).

18. See KSR, 550 U.S. 398.

19. Assuming that you are not going to simply abandon the application.

20. 37 C.F.R. § 1.321(b)(1).

21. Id. § 1.321(b)(2).

22. Id. § 1.321(b)(3).

23. Id. §§ 1.20(d), 1.321(b)(4).

24. Quad Envtl. Techs. Corp. v. Union Sanitary Dist., 946 F.2d 870 (Fed. Cir. 1991).

25. SimpleAir, Inc. v. Google LLC, 884 F.3d 1160 (Fed. Cir. 2018).

26. Eli Lilly & Co. v. Barr Labs., Inc., 251 F.3d 955 (Fed. Cir. 2001).

27. Japanese Found. for Cancer Research v. Lee, 773 F.3d 1300 (Fed. Cir. 2014); In re Dinsmore, 757 F.3d 1343 (Fed. Cir. 2014).

28. See Memorandum from Robert A. Clarke, Editor, MPEP, to Office of Petitions Staff (Aug. 15, 2017), https://www.uspto.gov/sites/default/files/documents/advance%20notice%20of%20change%20to%20MPEP%201490%208_15_2017.pdf.

29. See MPEP, supra note 1, § 706.02.

30. 37 C.F.R. § 1.321(c)(3).

31. 35 U.S.C. §§ 1.9(e), 100(h).

32. 37 C.F.R. § 1.104(c)(4)(ii), (5)(ii).

33. Id. § 1.321(d)(3).

34. But see MPEP, supra note 1, § 1490, ¶


Russell S. Timm, PhD, is a member of Womble Bond Dickinson’s life sciences and pharmaceuticals team. He has extensive experience in obtaining patents covering therapeutic antibodies and antibody-drug conjugates for clients, but also works on a wide variety of other technologies.

JD Wooten is a member of Womble Bond Dickinson’s IP, technology, and data team, where he assists clients in securing and protecting their creative rights in patent, trademark, and copyright matters, with a focus on civil litigation and other forms of IP enforcement.