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5 September 2025

Failure-to-Function – The Truly Scandalous F-Words

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The legal saga over the registration of the F-word and F-word derivatives as trademarks continues to push the development of trademark law in ways that apply well beyond the use of profanities as trademarks.
United States Intellectual Property

The legal saga over the registration of the F-word and F-word derivatives as trademarks continues to push the development of trademark law in ways that apply well beyond the use of profanities as trademarks. Many will recall that the Supreme Court inIancu v. Brunettistruck down the prohibition on registration of "immoral or scandalous matter" under the First Amendment, allowing Mr. Brunetti to register the mark FUCT and leading the USPTO to withdraw that basis for refusing his other applications for the F-word itself (yes, that F-word). But that was just the first round of the fight for Mr. Brunetti. The USPTO then refused registration of the F-word itself on grounds that the mark "fails-to-function" as a trademark. Mr. Brunetti appealed the USPTO's rejection and, inIn re: Brunetti, the Federal Circuit gave Brunetti another win—by vacating the USPTO's rejection based on an inadequate analysis.

The USPTO has long rejected trademark applications for "failure-to-function." This phrase is now a term of art referring to the fact that not every word, phrase, or design on a productfunctionsas a source identifier. As the Supreme Court recently explained inJack Daniel's Props., Inc. v. VIP Prods. LLC, "a trademark is not a trademark unless it identifies a product's source (this is a Nike) and distinguishes that source from others (not any other sneaker brand)." If the word, phrase, or design on a product does not function as a source identifier, it cannot be a trademark, and the USPTO should refuse registration. The USPTO issues "failure-to-function" refusals for many different reasons, including on grounds that the applied-for mark is informational, ornamental or, in this case, a widely used message.

But "failure-to-function" is not a self-defining standard, particularly when considering an intent-to-use application (i.e., when the USPTO has not seen how the mark is used). It is one thing to say that a word as displayed on a product does not function as a mark. It is another to say that the word canneverfunction as a mark. Here, the TTAB rejected Brunetti's registration of the F-word without knowing how he will use the term, finding that it could not function as a mark because applying it to an article would function merely as an expression of sentiment, not as a source identifier.

The Federal Circuit rejected Brunetti's challenge to the failure-to-function doctrine as a whole, but found the USPTO's analysis of Brunetti's application incomplete. The majority found that the TTAB's rejection amounted to an "I know it when I see it" approach that leads to inconsistent and unjust results. In particular, the Federal Circuit majority expressed dissatisfaction with the Board's analysis as to why this particular word could not function as a mark when numerous other commonly used English words are registered as marks every day and with its failure to provide clear guidance about the standard used to determine whether all-purpose word marks can be registered and which are inherently incapable of functioning as a source indicator. Although not dispositive, it was not lost on the court that the USPTO allowed other registrants to register the F-word for other goods (such as snow globes) without raising any failure-to-function issues.

In dissent, Judge Lourie expressed concern that the majority was ignoring the evidence (which showed that the F-word is widely used) and common sense understanding of how applying the particular word on a product would never really function as a source identifier. Instead, customers would buy products bearing the mark in order to express the word itself. By attempting to protect a common expressive word that nobody would see as functioning as a source identifier, Brunetti would then be allowed to monopolize the idea—something that trademark law should not permit.

The TTAB now must go back and articulate a test for this failure-to-function doctrine. And although they might not seek marks with quite the flair of Brunetti's, future trademark applicants will have to navigate the test the TTAB creates. With a clearly articulated test, it will hopefully be easier in the future for trademark owners and their attorneys to determine whether their marks are likely to be refused on this basis.

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