General

• Claims must not be identical, but they must have the same subject matter
• Inter partes proceeding between [2 patent applications] or [1 patent and 1 application]
• §1.131 cannot be used to “swear behind” a patent claiming the same invention; but it can be used to swear behind a patent disclosing same invention
• Senior party has earliest effective filing date and becomes the Defendant
• A party wins if they were first to conceive and diligent starting before the other party’s conception and later filing date

Provoking an Interference

• Applicant may provoke by: proposing a count (mock claim); presenting or identifying a claim (in an application) corresponding to count; identifying other pending application (issued patent); and explain why interference should be declared
• Applicant can copy a claim from another pending application or issued patent verbatim at the suggestion of examiner
• Timing – provoking an interference with an issued patent must normally be done less than one year from issue date; good faith EOT; if published and applicant’s filing date was after publication, the copying must be done less than one year from publication date
• When two applications are involved, examiner will not suggest copying if more than 3 months difference in filing dates if simple; and 6 months if not simple
• Once interference is filed, each party has access to opponent’s file
• If interfering applications or application/patent have the same inventive entity or common assignee, then double patenting rejection is proper
• Failure to comply with suggestion (usually non-extendable 1 month) acts as a disclaimer to uncopied subject matter
• Declarations must be filed only with an issued patent/pending application interference
• Parties may voluntarily settle before interference terminates by filing written agreement with PTO

Burden of Proof

• The issue in an interference between applications is normally priority of use, but the rights of the parties to registration may also be determined. The party whose application involved in the interference has the latest filing date is the junior party and has the burden of proof.
• When there are more than two parties to an interference, a party shall be a junior party to and shall have the burden of proof as against every other party whose application involved in the interference has an earlier filing date. If the involved applications of any parties have the same filing date, the application with the latest date of execution will be deemed to have the latest filing date and that applicant will be the junior party. The issue in an interference between an application and a registration shall be the same, but in the event the final decision is adverse to the registrant, a registration to the applicant will not be authorized so long as the interfering registration remains on the register.
  
• There is a higher standard of proof if the patent is already issued (clear and convincing) compared to if two applicants are pending (preponderance). See the PTO here, http://www.uspto.gov/web/offices/pac/mpep/documents/appxr_1_657.htm