PTAB May Be Preferred Forum to Assert Patent Priority-Claim Defects


PTAB May Be Preferred Forum to Assert Patent Priority-Claim Defects

It is well-known that the patent statutes provide patent applicants with the ability to claim priority to an earlier-filed provisional or non-provisional patent application by making “specific reference” to the earlier application.1

It is, however, less well-known that the United States Patent and Trademark Office (“USPTO”) has promulgated rules that limit the manner in which the patent applicant must comply with this requirement.2 The rules specify not only what the “specific reference” must be,3 but also where the “specific reference” must appear. The latter requirement has become more demanding over time.

Prior to September 16, 2012, the USPTO required the “specific reference” to appear in at least one of two places: (1) the Application Data Sheet (“ADS”) accompanying a patent application; or (2) the first sentence of the specification following the title. 37 C.F.R. § 1.78(a)(3), (d)(2), and (h). But a non-provisional patent application filed on or after September 16, 2012, must contain any priority claim in the ADS. Id. In other words, under USPTO regulations, a patent application filed after September 16, 2012 is not entitled to the benefit of a priority claim unless that priority claim is set forth in the ADS.

The USPTO’s priority rules have significant impacts for those litigating an issued patent. As explained below, these regulations can have real teeth, and a patentee’s failure to follow them may invalidate the patent. A patentee can usually correct a priority claim, but even then there can be consequences.

I. Impact of the USPTO’s Priority Rules

An invalid priority claim can result in an invalid patent. For example, when a patent unsuccessfully attempts to claim priority to an earlier application, the published or patented version of the earlier application can anticipate the patent. Reviewing the ADS of a patent granted on an application filed on or after September 16, 2012 is a simple but potentially powerful way to invalidate the patent: if the priority claim is not present in the ADS or if the priority claim is present but fails to comply with other requirements of the statutes and rules, then a patent challenger can argue the priority claim is invalid. And while patent challengers should check the validity of all priority claims, patents granted on applications filed on or after September 16, 2012, may be particularly likely to contain defective priority claims. First, patentees may have been operating under previous versions of the USPTO’s rules, which did not require a priority claim to appear in an ADS. Second, the ADS was and continues to be an otherwise optional part of a patent application.4

Decisions have not yet addressed the USPTO’s current rule requiring a priority claim to be made in the ADS. However, courts and the PTAB generally require an issued patent’s priority claim to comply with the USPTO’s rules. E.g., Worlds, Inc. v. Activision Blizzard, Inc., No. CIV.A. 12-10576-DJC, 2014 WL 972135 (D. Mass., Mar. 13, 2014); Simmons Inc. v. Bombardier, Inc., 328 F. Supp. 2d 1188 (D. Utah 2004); Apple Inc. v. E-Watch, Inc., IPR2015-00414, Paper 34 at *5-8 (June 22, 2016); E-Trade Fin. Corp. v. Droplets, Inc., IPR2015-00470, Paper 35 at *12 (June 23, 2016). A priority claim is usually ineffective if it fails to comply with USPTO rules.

The Worlds case addressed the previous version of the USPTO’s rules and held that a priority claim must appear in the place required by the rules. At issue in Worlds was the ‘045 Patent’s priority claim to an earlier provisional application. The ‘045 patent application did not contain a priority claim to the provisional in either place required by the rules, i.e., the ADS or the first sentence of the specification. The file wrapper of the ‘045 Patent, however, contained several documents explicitly claiming priority to the provisional application, including: (1) an application transmittal letter; (2) inventors’ declarations; and (3) a request for a corrected filing receipt. The court held that none of those documents were an ADS as defined by 37 C.F.R. § 1.76. The court thus held that the ‘045 Patent did not claim priority to the provisional because no priority claim was made in either of the two places permitted by the USPTO’s rules.

As Worlds illustrates, a failure to claim priority in the specific place required by the USPTO can be fatal to a priority claim. For patents issued on applications filed on or after September 16, 2012, the ADS is sole place the USPTO permits a priority claim to be made. Thus, one challenging such a patent should review the ADS and argue that priority is not warranted if the ADS fails to contain a “specific reference” that meets the USPTO’s requirements. In addition, when a patent claims priority to a chain of earlier applications, a challenger should review the ADS of each application filed after September 16, 2012, because a defective priority claim in any one of those applications infects all subsequent applications in the chain. Medtronic Corevalve LLC v. Edwards Lifesciences Corp., 741 F.3d 1359 (Fed. Cir. 2014).

II. Can Equity Save a Technically-Defective Priority Claim?

The USPTO’s strict requirement that a priority claim appear in an ADS may strike some as procedural nitpickiness. Will a priority claim really fail simply because it is made in the specification rather than in the ADS, or can equitable concerns outweigh compliance with the USPTO rules? The answer is not straightforward, and it can depend on the forum in which the patent is litigated.

Courts have announced a public-notice policy behind the priority statutes. E.g. Carotek, Inc. v. Kobayashi Ventures, LLC, 875 F. Supp. 2d 313, 335 (S.D.N.Y. 2012)(“The purpose of the ‘specific reference’ requirement is clearly to ensure that someone examining a patent claiming the benefit of one earlier filed is readily able to assess the patent’s priority date.”) District courts occasionally rely on that policy to deem valid a technically defective priority claim.5 But it is not clear that the PTAB could use this type of equitable approach to condone a violation of the USPTO’s rules, much less that it would be likely to do so even if it could.

An agency is typically required to follow its own rules.6 E.g., Wagner v. United States, 365 F.3d 1358, 1361 (Fed. Cir. 2004). The question, then, is whether the PTAB has the legal authority to deem valid a priority claim that fails to comply with the USPTO’s priority rules. There are two potential sources for that authority, but neither source has been established. First, 37 C.F.R. § 1.183 permits the Director to waive any USPTO rule “[i]n an extraordinary situation, when justice requires.” However, it is not clear that the Director has delegated this authority to the PTAB. See M.P.E.P. 1002(b). Second, 37 C.F.R. § 42.5(b), titled “Conduct of the Proceeding,” permits the PTAB to “waive or suspend a requirement” of Part 1 of the C.F.R. It remains to be seen whether the PTAB’s authority under 42.5(b) extends beyond rules governing a trial’s proceedings to substantive rules governing patent rights.

In sum, asserting equitable arguments to overcome non-compliance with the USPTO’s priority rules seems better targeted to district courts than to the PTAB.

III. Correcting an Erroneous Priority Claim

A defective priority claim can ordinarily be corrected by reissue or a certificate of correction. Both options have downsides – particularly when a PTAB Trial is ongoing, as the PTAB can and often will stay proceedings to obtain either type of relief. Thus, early attention to defective priority claims is the best strategy: priority claims should be reviewed during prosecution and immediately after a patent issues, and any defect should be cured as soon as possible.

A. Correction by certification of correction

An error introduced by a patent applicant can be corrected pursuant to 35 U.S.C. § 255 as long as those errors are “clerical” or “of minor character.”7 Many courts have upheld certificates of correction used to correct a priority claim.8 This approach does have one major drawback: a certificate of correction is only valid for acts of infringement that occur after the certificate issues. Southwest Software, Inc. v. Harlequin Inc., 226 F.3d 1280, 1295 (Fed. Cir. 2000). If the patent contains a fatally defective priority error, then the patentee cannot recover for previous acts of infringement because the pre-correction patent is invalid. Worlds, 2014 WL 972135, at *9-10.

A patentee can ordinarily submit a request for a certificate of correction any time after a patent issues. If, however, a patentee requests correction of a patent that is also subject to a Trial before the PTAB, then the patentee must also file a motion with the PTAB seeking correction.9 37 C.F.R. §§ 1.322(a)(3), 1.323. The PTAB does not grant such motions as a matter of course.10

B. Correction by reissue

Courts have long recognized that reissue under 35 U.S.C. § 251 is an appropriate way to correct a priority claim.11 Reissue has two statutory requirements.12 First, reissue can only be used when a patent is wholly or partly inoperative or invalid by reason of a defective specification or drawing, or by reason of the patentee claiming more or less than he had a right to claim. Several cases find that a defective priority claim meets this requirement.13 Second, a reissued patent that would “enlarg[e] the scope of the claims” is only permitted if reissue is sought within two years of the original patent grant. While infrequently addressed, it appears settled that correcting a priority claim does not enlarge the scope of the claims under the meaning of 35 U.S.C. § 251. Fontijn v. Okamoto, 518 F.2d 610, 621 (C.C.P.A. 1975) (addressing a priority claim to a foreign application). Thus, reissue to correct a priority claim can be sought at any time.

One major advantage of reissue is that, unlike a certificate of correction, a patentee is not automatically cut off from recovering on infringement prior to reissue. However, reissue can hinder a patent’s enforceability: under 35 U.S.C. § 252, an infringer has an absolute right to avoid past infringement (and certain instances of future infringement) of a reissued patent claim that was not in the original patent. An infringer can also seek ongoing equitable intervening rights if “substantial preparation” for the infringement was made before the reissue patent issues. In what appears to be the only opinion addressing intervening rights for a reissue that corrects priority defects, a court held that correcting a priority claim does not trigger absolute intervening rights (because the reissued claims and original patent claims are identical) and found that reliance on the defective priority claim (or lack thereof) was necessary to grant intervening equitable rights. Lucent Techs. Inc. v. Gateway, Inc., No. CIV.02CV2060-B(CAB), 2007 WL 925507, at *6-11 (S.D. Cal. Mar. 19, 2007). Thus, reissue can avoid the infringement consequences that automatically come with a certificate of correction.

Reissue has at least one major downside: a request for reissue re-opens prosecution as to all matters. Thus, while a patentee may seek reissue for the limited purpose of correcting a priority claim, the claims of the patent may be reexamined for compliance with any and all patentability requirements. That may be particularly concerning for patentees when patentability requirements become more demanding after the original patent issued.14

Procedurally, the PTAB governs whether, and on what terms, a request for reissue will be granted on a patent at issue in a trial. 37 C.F.R. §§ 42.3, 42.122(a). Thus, a patentee requesting reissue to correct an erroneous priority claim should make its request as soon as the error is discovered.

IV. Conclusion

The USPTO’s rules for perfecting a priority claim are more restrictive than the patent statute suggests. Parties accused of infringement should consider whether a defective priority claim strengths an invalidity case and whether a priority claim is better challenged in the PTAB than in district court. Similarly, patent owners should carefully review their priority claims before asserting a patent and determine the best approach to correcting any defect in the priority claim.


1 See 35 U.S.C. §§ 119(e) and 120 (“an application for patent . .. shall have the same effect . . . as though filed on the date of the provisional application … if it contains or is amended to contain a specific reference to [the earlier filed application].”).
2 37 C.F.R. § 1.78(a)-(c) (post-AIA) addresses a priority claim made to a provisional application, and § 1.78(d)-(e) (post-AIA) addresses a priority claim made to a non-provisional application. Unless indicated otherwise, all references to Title 37 of the C.F.R. are to the post-AIA version of the rules.
3 E.g., 37 C.F.R. § 1.78(d)(2) (requiring a priority claim made under Section 120 to identify the prior application by serial number and identify the relationship between the two applications.).
4 37 C.F.R. § 1.76(a); M.P.E.P. 601.05.
5 See, e.g., Prism Techs. LLC v. AT&T Mobility, LLC, No. 8:12CV122, 2013 WL 12120391, at *10 (D. Neb. May 20, 2013) (finding valid a priority claim that appeared on the front page of a published patent application but was not in an ADS or the first sentence of the specification.)
6 This appears to be settled law at least for rules an agency promulgates under the Administrative Procedures Act, e.g., rules made through the notice-and-comment provisions of 5 U.S.C 553. For a much more detailed discussed of an agency’s ability to deviate from its own rules, see Charles H. Koch, Jr. and Richard Murphy, Admin. L. & Prac. § 4:22 (3rd ed.).
7 35 U.S.C. § 254 permits correction of errors made by the USPTO. Errors in priority claims are more commonly made by applicants than by the USPTO, and thus this article focuses on Section 255.
8 E.g., Carotek, Inc. v. Kobayashi Ventures, LLC, 875 F. Supp. 2d 313, 331-35 (S.D.N.Y. 2012); Word to Info, Inc. v. Google Inc., 140 F. Supp. 3d 986, 988 (N.D. Cal. 2015); B. Braun Melsungen AG v. Becton, Dickinson & Co., No. 1:16-CV-411-RGA, 2017 WL 2531939 (D. Del. June 9, 2017).
9 The PTAB has held that permission must be requested, and that it has the authority under 42.3 to stay a request for correction, even when a trial has been petitioned for but not yet instituted. Inc. IPR2016-00116, Paper No. 9 (January 28, 2016).
10 E.g., Douglas Dynamics, L.L.C. v. Meyer Products, LLC, IPR2015-01839, Paper 51 (Mar. 1, 2017) (denying a motion to correct based on prejudice to the petitioner and the patentee’s tardiness in waiting 15 years from issue to request correction); Kingston Tech. Co., Inc. v. CATR Co., LTD, IPR2015-00559, Paper 44 (Nov. 6, 2015) (denying a motion to correct based on prejudice to the petitioner and because the patentee previously sought a certificate of correction that did not address the correction moved for).
11 Indeed, reissue of a child application along with revival of a parent application may be the only way to fix a priority claim to a parent that was abandoned before the child application was filed. E.g., Avanir Pharm., Inc. v. Actavis S. Atl. LLC, 987 F. Supp. 2d 504, 510-512 (D. Del. 2013) (holding that co-pendency is a statutory requirement that cannot be waived by courts or the USPTO). But see Pfizer Inc. v. Teva Pharm. U.S.A., Inc., 882 F. Supp. 2d 643, 696-98 (D. Del. 2012) (holding that a certificate of correction could cure a 1-day gap in co-pendency).
12 Note, however, that the USPTO requires a reissue request that corrects a priority claim to be accompanied by a petition for a delayed priority claim. M.P.E.P. 1402.IV.
13 Fontijn v. Okamoto, 518 F.2d 610 (C.C.P.A. 1975); Sampson v. Comm’r of Patents & Trademarks, No. 75-0901, 1976 WL 20992, at *1 (D.D.C. Nov. 10, 1976); Lucent Techs. Inc. v. Gateway, Inc., No. CIV.02CV2060-B(CAB), 2007 WL 925507, at *6-11 (S.D. Cal. Mar. 19, 2007). However, reissue cannot be used to “correct” a priority claim that was intentionally never sought. In re Serekin, 479 F.3d 1359, 1364 (Fed. Cir. 2007).
14 Consider, for example, the impact on patentable subject matter caused by Alice Corp. Pty. v. CLS Bank Int’l, 134 S. Ct. 2347 (2014).

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