Source: https://www.uspto.gov/web/offices/pac/mpep/s2301.html
Timestamp: 2019-04-20 11:37:20+00:00

Document:
An interference is a contest under pre-AIA 35 U.S.C. 135(a) between an application and either another application or a patent. An interference is declared to assist the Director of the United States Patent and Trademark Office in determining priority, that is, which party first invented the commonly claimed invention within the meaning of pre-AIA 35 U.S.C. 102(g)(1). See MPEP § 2301.03. Once an interference has been suggested under 37 CFR 41.202, the examiner refers the suggested interference to the Board. An administrative patent judge declares the interference, which is then administered at the Board. A panel of Board members enters final judgment on questions of priority and patentability arising in an interference.
Once the interference is declared, the examiner generally will not treat the application again until the interference has been terminated. Occasionally, however, the Board may refer a matter to the examiner or may consult with the examiner on an issue. Given the very tight deadlines in an interference, any action on a consultation or referral from the Board must occur with special dispatch.
Given the infrequency, cost, and complexity of interferences and derivation proceedings, it is important for the examiner to consult immediately with an Interference Practice Specialist (IPS) in the examiner’s Technology Center, see MPEP § 2302, once a possible interference is identified. It is also important to complete examination before the possible interference is referred to the Board. See MPEP § 2303. See MPEP § 2310et seq. for discussion of derivation proceedings.
35 U.S.C. 104 (pre-AIA) Invention made abroad.
(1) PROCEEDINGS.—In proceedings in the Patent and Trademark Office, in the courts, and before any other competent authority, an applicant for a patent, or a patentee, may not establish a date of invention by reference to knowledge or use thereof, or other activity with respect thereto, in a foreign country other than a NAFTA country or a WTO member country, except as provided in sections 119 and 365 of this title.
37 CFR 41.200 Procedure; pendency.
(b) Any reference to 35 U.S.C. 102 or 135 in this subpart refers to the statute in effect on March 15, 2013, unless otherwise expressly indicated. Any reference to 35 U.S.C. 141 or 146 in this subpart refers to the statute applicable to the involved application or patent.
Constructive reduction to practice means a described and enabled anticipation under 35 U.S.C. 102(g)(1), in a patent application of the subject matter of a count. Earliest constructive reduction to practice means the first constructive reduction to practice that has been continuously disclosed through a chain of patent applications including in the involved application or patent. For the chain to be continuous, each subsequent application must comply with the requirements of 35 U.S.C. 119-121, 365, or 386.
Involved claim means, for the purposes of 35 U.S.C. 135(a), a claim that has been designated as corresponding to the count.
(ii) Unpatentability for lack of written description under 35 U. S.C. 112 of an involved application claim where the applicant suggested, or could have suggested, an interference under § 41.202(a).
A claim of one inventor can be said to interfere with the claim of another inventor if they each have a patentable claim to the same invention. The Office practice and the case law define “same invention” to mean patentably indistinct inventions. See Case v. CPC Int’l, Inc., 730 F.2d 745, 750, 221 USPQ 196, 200 (Fed. Cir. 1984); Aelony v. Arni, 547 F.2d 566, 570, 192 USPQ 486, 489-90 (CCPA 1977); Nitz v. Ehrenreich, 537 F.2d 539, 543, 190 USPQ 413, 416 (CCPA 1976); and Ex parte Card, 1904 C.D. 383, 384-85 (Comm’r Pats. 1904). If the claimed invention of one party is patentably distinct from the claimed invention of the other party, then there is no interference-in-fact. See Nitz v. Ehrenreich, 537 F.2d 539, 543, 190 USPQ 413, 416 (CCPA 1976). 37 CFR 41.203(a) states the test in terms of the familiar concepts of obviousness and anticipation. See Tas v. Beachy, 626 Fed. App'x. 999, 1001 (Fed. Cir. 2015)(nonprecedential) (an interference exists if the subject matter of a claim of one party would, if prior art, have anticipated or rendered obvious the subject matter of a claim of the opposing party and vice versa); Eli Lilly & Co. v. Bd. of Regents of the Univ. of Wa., 334 F.3d 1264, 1269-70, 67 USPQ2d 1161, 1164-65 (Fed. Cir. 2003) (affirming the Office’s interpretive rule).
Identical language in claims does not guarantee that they are drawn to the same invention. Every claim must be construed in light of the application in which it appears for purpose of evaluating whether there is interfering subject matter, unlike when evaluating whether copied claims comply with the written description requirement where the originating disclosure is consulted. See Agilent Techs., Inc. v. Affymetrix, Inc., 567 F.3d 1366, 1375, 91 USPQ2d 1161, 1167 (Fed. Cir. 2009) (when a party challenges written description support for a copied claim in an interference, the originating disclosure provides the meaning of the pertinent claim language). Claims reciting means-plus-function limitations, in particular, might have different scopes depending on the corresponding structure described in the written description.
When an interference is declared, there is a description of the interfering subject matter, which is called a “count.” Claim correspondence identifies claims that would no longer be allowable or patentable to a party if it loses the priority determination for the count. To determine whether a claim corresponds to a count, the subject matter of the count is assumed to be prior art to the party. If the count would have anticipated or supported an obviousness determination against the claim, then the claim corresponds to the count. See 37 CFR 41.207(b)(2). Every count must have at least one corresponding claim for each party, but it is possible for a claim to correspond to more than one count.
Applications subject to current 35 U.S.C. 102 (see MPEP § 2159) may also be subject to an interference.
Even if current 35 U.S.C. 102 and 103 apply to a patent application, pre-AIA 35 U.S.C. 102(g) also applies to every claim in the application if it: (1) contains or contained at any time a claimed invention having an effective filing date as defined in 35 U.S.C. 100(i) that occurs before March 16, 2013; or (2) is ever designated as a continuation, divisional, or continuation-in-part of an application that contains or contained at any time such a claim. Pre-AIA 35 U.S.C. 102(g) also applies to any patent resulting from an application to which pre-AIA 35 U.S.C. 102(g) applied. See MPEP §§ 2138 and 2159.03.
Thus, if an application contains, or contained at any time, a claim having an effective filing date that occurs before March 16, 2013, and also contains, or contained at any time, a claim having an effective filing date that is on or after March 16, 2013, each claim may still be subject to an interference in accordance with pre-AIA 35 U.S.C. 102(g) while the application is also subject to current 35 U.S.C. 102 and 103. Pub. L. 112-29, § 3(n)(2), 125 Stat. at 293.
Where an application not subject to pre-AIA 35 U.S.C. 102(g) interferes with a patent subject to pre-AIA 35 U.S.C. 102(g), the examiner should consult with an Interference Practice Specialist.

References: § 2301
 § 2302
 § 2303
 § 2310
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 § 2159
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