1005 Burden of Proof
37 CFR § 2.96 Issue; burden of proof. . ... 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. ... .
37 CFR § 2.116(b) ... A party that is a junior party in an interference proceeding or in a concurrent use registration proceeding shall be in the position of plaintiff against every party that is senior, and the party that is a senior party in an interference proceeding or in a concurrent use registration proceeding shall be a defendant against every party that is junior.
In an interference proceeding, the party whose involved application has the latest filing date is the junior party. When there are three or more parties to an interference, a party is a junior party to every other party whose involved application 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 is deemed to have the latest filing date, and that applicant is the junior party. [ Note 1.]
A junior party in an interference proceeding is in the position of plaintiff, and has the burden of proof, as against every party that is senior, that is, as against every party whose involved application has an earlier filing date. Conversely, a senior party is in the position of defendant as against every party that is junior, that is, as against every party whose involved application has a later filing date. [ Note 2.] For information concerning joining or substituting a transferee when there has been an assignment of a mark which is involved in an interference proceeding, see TBMP § 512.01.
NOTES:
2. 37 CFR § 2.96 and 37 CFR § 2.116(b). See also Jim Dandy Co. v. Martha White Foods, Inc., 458 F.2d 1397, 173 USPQ 673, 674 (CCPA 1972); McNeil v. Mini Mansions, Inc., 178 USPQ 312, 314 (TTAB 1973).