A word that fails to distinguish goods or services does not meet the statutory definition of a trademark, and thus cannot be registered. 15 U.S.C. §§ 1051, 1127; see also In re Standard Oil Co., 275 F.2d 945, 125 USPQ 227, 228 (CCPA 1960 (“The Trademark Act is not an act to register words but to register trademarks.”). 

The Federal Circuit recently held that the Trademark Trial and Appeal Board (“TTAB”) failed to articulate a clear standard and explanation why the word FUCK cannot function as a trademark. In re Brunetti, No. 23-1539, __ F.4th __ (Fed. Cir. Aug. 26, 2025). 

The TTAB had found that the marketplace was awash in products that display the term FUCK as a prominent ornamental feature of such goods, along with copious evidence of websites in the marketplace offering goods with the term FUCK to consumers as relevant evidence of consumer perception of FUCK as an all-purpose word. [TTAB decision previously blogged here]. 

The Federal Circuit, however, found that the TTAB failed to provide rational guidance that is sufficiently explained for the refusal to register Brunetti's FUCK mark. 

The Board determined that Mr. Brunetti failed to meet a standard, but it did not articulate what that standard would be. In other words, the Board's decision is unclear as to the circumstances under which all-purpose word marks can be registered and which are “inherently incapable of being regarded as [a] source indicator[].” S. App'x 34–35.
     The Board's reasoning in this case suggests that the Board has concluded that it need not articulate a viable registration standard. The apparent inconsistency of past examining attorneys' decisions with respect to the registration of all-purpose word marks is itself strong evidence of the failure to articulate coherent rules and engage in reasoned decisionmaking. 
     The Board's reasoning sounds in fact very much as though it has taken an “I know it when I see it” approach to failure-to-function refusals. Such an approach is inconsistent with the Board's mandate to engage in reasoned decisionmaking under the APA. Pearson v. Shalala, 164 F.3d 650, 660–61 (D.C. Cir. 1999) (holding invalid FDA's interpretation of regulation where FDA took “I know it when I see it” approach to the term “significant scientific agreement”); Stanojkova v. Holder, 645 F.3d 943, 949 (7th Cir. 2011), as amended (Aug. 16, 2011) (explaining that “I know it when I see it” approach of the Board of Immigration Appeals resulted in “capricious adjudication”); see also In re Scheer, 819 F.3d 1206, 1210 (9th Cir. 2016) (“It is fair to say that the ‘I know it when I see it approach' of [a prior precedent] has led to predictably unpredictable results.”)

The Federal Circuit concluded the TTAB “failed to provide sufficient precision in its rationale for why some commonplace words can serve as a mark, but others, such as FUCK, cannot.” The Court further noted that this lack of clarity “is especially troubling given the increasing number of failure-to-function refusals in recent years.” And the Court noted the Supreme Court's admonition that the USPTO must consider its “own past practice” in developing a “comprehensive rule,” citing United States Pat. & Trademark Off. v. Booking.com B.V., 591 U.S. 549, 558 (2020). Thus, the case was remanded back to the TTAB for further proceedings. 

In dissent, Judge Lourie acknoweldged the "shortcomings in the Board's analysis of the failure to function issue," but would have affirmed that decision because of FUCK's "ubiquity" such that "consumers cannot specifically associate the word with Brunetti's brand."