Obviousness-type double patenting ("ODP") is a judicially-created doctrine1 intended to prevent the unjustified extension of the right to exclude granted by a patent.2 See In re Hubbell, 709 F.3d 1140, 1145 (Fed. Cir. 2013). The Court of Appeals for the Federal Circuit ("CAFC") has addressed the applicability of ODP several times in the last decade, but ODP finds its roots in decisions from the CAFC's predecessor, the Court of Customs and Patent Appeals ("CCPA").

Indeed, the CAFC recently noted that "[t]he prohibition against double patenting is a longstanding doctrine of patent law" that federal courts have applied "for over a century." Gilead Sciences, Inc. v. Natco Pharma Ltd., 753 F.3d 1208, 1212 (Fed. Cir. 2014). As part of our continuing series analyzing CCPA precedent, this article analyzes several key CCPA decisions regarding ODP that contributed to today's ODP jurisprudence. While we will be focusing on a handful of key decisions, the CCPA issued numerous opinions concerning ODP that remain binding precedent and, therefore, relevant today.3

Today's ODP case law traces its origins to Judge Rich's concurrence in In re Zickendraht, 319 F.2d 225 (C.C.P.A. 1963). In that case, the Examiner rejected the claims of a pending application because they were not patentably distinguishable from the claims in an earlier-issued patent having the same named inventor. Zickendraht, 319 F.2d at 226-27. Finding that the differences in the claims were not patentably distinct, the CCPA affirmed the rejection, concluding that "there is but one patentable invention." Id. at 228. In concurrence, Judge Rich agreed that the claims should have been rejected for double patenting but disagreed with the basis for the court's conclusion. Id. at 229. He explained that "[t]here is an important difference between the situation where there is one invention being twice claimed and the situation, as here, where there are two inventions and one is unpatentable over the other." Id. at 230-31. He summarized the rule as follows: "claims to inventions closely related to the invention claimed in a patent and not patentably distinguishable therefrom must be included in the same patent unless the applicant has been forced to make them in a separate application by a requirement of restriction." Id. at 232. While he avoided opining on the impact a terminal disclaimer might have had in this case, Judge Rich did note that an applicant may be able to avoid a double patenting rejection by filing a terminal disclaimer. Id.

The CCPA had an opportunity to consider the impact of a terminal disclaimer in In re Robeson, 331 F.2d 610 (C.C.P.A. 1964). In that case, the Examiner rejected the claims of a pending application because they were not patentably distinguishable from the claims in an earlier-issued patent having the same named inventor, despite the fact that the applicant had filed a terminal disclaimer. Robeson, 331 F.2d at 611-613. The Court began by explaining that one of the "fundamental principles underlying the patent system" is "that when the right to exclude granted by a patent expires at the end of the term, the public shall be free to use the invention as well as obvious modifications thereof or obvious improvement thereon. Id. at 614. Thus, to grant a second patent for an obvious variant deprives the public of those rights." Id. However, in reversing the Examiner's double patenting rejection, the Court explained that a terminal disclaimer precludes any extension because the second patent would expire simultaneously with the first. Id.

Several years later the CCPA issued its decision in In re Vogel, 422 F.2d 438 (C.C.P.A. 1970). This case is one of the most frequently cited ODP cases from the CCPA, which is likely due, at least in part, to its clear outline of the two-prong double patenting analysis. Vogel, 422 F.2d at 441. First, the Court asks whether the same invention (i.e., identical subject matter) is being claimed twice. If the answer is yes, then 35 U.S.C. § 101 prohibits the grant of a second patent. Id. This is also known as statutory double patenting.

If, however, the same invention is not being claimed twice, then the Court asks whether the application is claiming an obvious variation of the invention claimed in the earlier-issued patent. Id. If the answer is no, then there is no double patenting, and a terminal disclaimer is not required. Id. If the answer is yes, then a terminal disclaimer is required to prevent an undue extension of the right to exclude. Id.

While Zickendraht, Robeson, and Vogel underpin today's ODP case law, there are several other cases that practitioners should be aware of and keep in their toolbox should they face an ODP argument by an examiner, at the Patent Trial and Appeal Board (PTAB), in the district court, or in the International Trade Commission. For example, In re Baird, 348 F.2d 974 (C.C.P.A. 1965) is a useful case when facing an ODP argument that relies on the specification of the earlier-issued patent. The Court in Baird explained that "the patent disclosure is not 'prior art' and cannot be looked to for what it teaches." Baird, 348 F.2d at 979. The specification may be considered to the extent necessary to understand what the words in the claim mean, but for nothing more. Id. at 979-80.

As another example, In re Sarett, 327 F.2d 1004 (C.C.P.A. 1964) is a useful case for a party facing an ODP argument for a claim that is subsumed within or "dominated by" the claims of the ODP reference (e.g., a species claim vs. a genus claim). In that case, the application included a claim directed to a specific oxidizing agent while the earlier-issued patent claimed an oxidizing agent generally. Sarett, 327 F.2d at 1014. The Court explained that the claims--one directed to a broad genus and the other a narrow species--were patentably distinct and the Examiner erred in rejecting the claims merely because they were subsumed or dominated by the claims of the earlier-issued patent. Id. at 1014-15.

As a final example, In re Boylan, 392 F.2d 1017 (C.C.P.A. 1968) is a useful case when facing an ODP argument for a method of use claim where the reference patent contains claims directed to a composition that could be used in the method. In that case, the application claimed a process for inhibiting foaming in an aqueous system. Boylan, 392 F.2d at 1019. The claims of the earlier-issued patent were directed to a defoaming composition or method of making a defoaming composition. Id. at 1019. The Court explained that the claims were directed to different, albeit related, subject matter and thus the ODP rejection was improper. Id. at 1022-23. The Court further explained that the Examiner erred in concluding that a double patenting rejection was proper merely because the patented composition could be used in the claimed process. Id.

These are but a few examples of cases decided long ago by the CCPA that remain relevant today. The CCPA issued many decisions concerning the applicability of obviousness-type double patent in a variety of circumstances, including ones that still arise today. Since these decisions remain good law, it is advantageous for practitioners to familiarize themselves with CCPA cases so that they have the cases at their disposal to overcome ODP rejections and attacks.


1. In contrast, same-invention double patenting is is rooted in 35 U.S.C. §101 which allows for one patent per invention ("Whoever invents or discovers...may obtain a patent therefor." (emphasis added).

2. A prohibition on multiple patents on obvious variants is a principle developed in light of this statutory rule. Abbvie, Inc. v. Kennedy Institute of Rheumatology Trust, 764 F.3d 1366, 1372 (Fed. Cir. 2014) ("'a rejection based upon double patenting of the obviousness type' is 'grounded in public policy (a policy reflected in the patent statute).'").

3. Between 1963 and 1982, the CCPA issued a significant number of decisions concerning ODP. The vast majority of these decision have not been overruled by the CCPA or overturned by an en banc Court of Appeals for the Federal Circuit ("CAFC") and thus remain binding precedent. See South Corp. v. U.S., 690 F.2d 1368, 1369 (Fed. Cir. 1982). Notably, many involved appeals from ex parte prosecution and are cited in the MPEP and, therefore, may be especially useful in responding to examiner rejections.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.