37 CFR § 41.208 - Content of substantive and responsive motions.
The general requirements for motions in contested cases are stated at § 41.121(c).
(a) In an interference, substantive motions must:
(1) Raise a threshold issue,
(2) Seek to change the scope of the definition of the interfering subject matter or the correspondence of claims to the count,
(3) Seek to change the benefit accorded for the count, or
(4) Seek judgment on derivation or on priority.
(b) To be sufficient, a motion must provide a showing, supported with appropriate evidence, such that, if unrebutted, it would justify the relief sought. The burden of proof is on the movant.
(1) A party moving to add or amend a claim must show the claim is patentable.