TMEP § 1215.05(b)(ii)
If the application itself or a subsequent submission requests registration on the Supplemental Register, and the evidence supports a determination that the proposed generic.com term is generic, registration must be refused under Trademark Act Sections 23(c) and 45, 15 U.S.C. §§1091(c), 1127. See TMEP §1209.02(a)(i).
If the examining attorney determines that the available evidence establishes that the proposed generic.com term is at least capable of indicating source but is insufficient to show that the term has acquired distinctiveness, the examining attorney may allow registration on the Supplemental Register, if otherwise appropriate. See TMEP §§815-815.02.