38 C.F.R. § 20.500
Link to an amendment published at 84 FR 183, Jan. 18, 2019.
In a simultaneously contested claim, any claimant or representative of a claimant may file a Notice of Disagreement or Substantive Appeal within the time limits set out in Rule 501 (§ 20.501 of this part).
(Authority: 38 U.S.C. 7105(b)(2), 7105A)