Trademark Act §7(b), 15 U.S.C. §1057(b), provides that a certificate of registration on the Principal Register shall be prima facie evidence of the validity of the registration, of the registrant’s ownership of the mark, and of the registrant’s exclusive right to use the mark in commerce in connection with the goods or services specified in the certificate. "The presumption of validity is not conditional; the statute provides that a certificate of registration 'shall' result in the presumption, without specifying any exceptions." SoClean, Inc. v. Sunset Healthcare Sols., Inc., 52 F.4th 1363, 1369 (Fed. Cir. 2022).

During ex parte prosecution, an applicant will not be heard on matters that constitute a collateral attack on the cited registration (e.g., a registrant’s nonuse or ownership of the mark). See In re Detroit Athletic Co., 903 F.3d 1297, 1309 (Fed. Cir. 2018) (noting that applicant’s objection to the breadth of the goods or trade channels described in the cited registration "amounts to an attack on the registration's validity" and that "the present ex parte proceeding is not the proper forum from which to launch such an attack," which is "better suited for resolution in a cancellation proceeding"); In re Dixie Rests., Inc., 105 F.3d 1405, 1408, 41 USPQ2d 1531, 1534-35 (Fed. Cir. 1997); In re Ye Mystic Krewe of Gasparilla, Ser. No. 90522364, 2025 TTAB LEXIS 412, at *25 n.22 (2025); In re Fiesta Palms, LLC, Ser. No. 76595049, 2007 TTAB LEXIS 51, at *7 (2007) ; In re Peebles Inc., Ser. No. 74073163, 1992 TTAB LEXIS 21, *7 n.5 (1992) ; In re Pollio Dairy Prods. Corp., Ser. No. 73596577, 1988 TTAB LEXIS 45, at *7 (1988) .

It is also inappropriate for the applicant in an ex parte proceeding to place the burden of showing a likelihood of confusion on the owner of the cited registration. In re Majestic Distilling Co., 315 F.3d 1311, 1318 (Fed. Cir. 2003) ("'It is the duty of the PTO and this court to determine whether there is a likelihood of confusion between two marks. . . . [I]t is no answer for the applicant to ask that the application be passed to publication to see whether the owner of the cited mark will oppose the registration.'" (quoting Dixie Rests., 105 F.3d at 1408)).