Restriction requirements under 35 U.S.C. § 121 arise during examination at the U.S. Patent and Trademark Office (USPTO) when an examiner determines that an applicant is pursuing multiple, patentably distinct inventions within the same application. The examiner's determination, however, may not always be in agreement with that of a court. In litigation, an accused infringer may assert that the patentee pursued the same or obviously similar inventions in multiple applications, one or more of which later issued as the patent-in-suit. A finding of double patenting can invalidate the offending claims. To account for this possible anomaly, 35 U.S.C. § 121 includes a safe harbor against double patenting, whereby "[a] patent issuing on an application with respect to which a requirement for restriction under this section has been made, or on an application filed as a result of such a requirement, shall not be used as a reference . . . 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."
Satisfying the safe-harbor provision requires that the divisional application maintain "consonance" with the parent and other reference patent. This judicially created consonance concept specifies that the "line of demarcation between 'independent and distinct inventions' that prompted the restriction requirement be maintained." Gerber Garment Tech., Inc. v. Lectra Sys., Inc., 916 F.2d 683, 688 (Fed. Cir. 1990). In other words, for the safe harbor to apply, a "divisional application filed as a result of a restriction requirement may not contain claims drawn to the invention . . . elected and prosecuted in the parent application." Id. at 687. While this concept seems clear in practice, its application can be complicated for more complex patent families.
The Court of Appeals for the Federal Circuit recently considered the scope of the safe-harbor provision for a family of four patents in St. Jude Medical, Inc. v. Access Closure, Inc., No. 12-1452 (Fed. Cir. Sept. 11, 2013). In the district court, St. Jude brought suit against Access Closure alleging patent infringement. The jury found that the claims-at-issue were invalid for double patenting.
The patent-in-suit was part of a family including a grandparent, parent, and one sibling. The examiner of the grandparent application had concluded that its claims were drawn to at least two patentably distinct inventions, a device and a method. In addition, the examiner stated that the device and method claims included patentably distinct Species A, B, and C. The applicant elected device claims and Species B. The applicant then filed the parent application, a divisional of the grandparent, and the examiner imposed substantially the same restriction and election of species requirements. In response, the applicant again elected device claims and Species B. The applicant then filed a first continuation of the parent, and, in doing so, canceled the original claims and, notably, added new device and method claims. The applicant eventually filed a second continuation, a sibling, based on the parent application. All four of the patents issued. The first continuation application, called "Janzen," was the patent-in-suit. The Janzen patent ultimately issued with claims directed to both devices and methods and to Species C, while its sibling patent issued with claims directed to methods.
With this history, the district court found the safe-harbor provision applied as between Janzen and its sibling (the second continuation), thus overturning the jury's invalidity finding. ACI appealed.
On appeal, the Federal Circuit reversed, holding the safe-harbor provision did not apply between Janzen and its sibling. The Court found that, for the safe harbor to apply, the challenged patent (Janzen), the reference patent (the sibling), and the restricted patent (the grandparent) must not claim any of the same inventions identified by the examiner. Notably, the Court also held that, in addition to the device/method restriction requirement, the election of species requirement between Species A, B, and C also affected the line of demarcation.
The Court held that the claims of Janzen were not independent and distinct from those of its sibling. The Janzen application pursued claims directed to both devices and methods and Species C. The sibling application, however, contained method claims generic to Species A, B, and C. Thus, because of the overlap of Species C between Janzen and the sibling, the Court held that the safe-harbor provision did not apply and that the claims-at-issue in Janzen were invalid.
In a concurring opinion, Judge Lourie found the case should have been resolved by the failure of both the granted Janzen and sibling patents to maintain "consonance" with the original restriction requirement in the grandparent application. The restriction requirement required dividing claims to devices from claims to methods, and the Janzen patent contained both device and method claims.
In addition to clarifying application of the safe-harbor provision, St. Jude Medical highlights the distinction between divisional and continuation applications. Divisional applications only result from a restriction requirement, but continuation applications are voluntary. This distinction is important when planning a patent family and analyzing whether a child application will be subject to double patenting. Further complicating matters, St. Jude Medical clarifies that, in some cases, an elected species can affect the line of demarcation. Thus, in developing a patent strategy, it is important to consider the type of applications being filed, whether there is an election of species, and how that election can impact whether a patent qualifies for the safe-harbor provision of 35 U.S.C. § 121.
Patent practitioners should also note that, in the United States, unlike in some other jurisdictions, the double patenting is curable by filing a terminal disclaimer. A terminal disclaimer may be filed at any time during the patent term, including in preparation for litigation. Thus, prior to enforcing or licensing a patent family, practitioners should consider whether there could be double patenting found between any of the patents in the family and if terminal disclaimers should be filed to eliminate such double-patenting concerns. When the patents-at-issue have different patent terms, however, the filing of a terminal disclaimer in the patent with the longer term will shorten its term and can accordingly affect its enforceability and value. Thus, the effect of the terminal disclaimer on the patent's enforceability should also be considered and balanced against the risk of a finding of double patenting.
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