## Facts

- Brunswick Corp. (Mercury Marine) applied to register the color black for outboard marine engines on the Principal Register under Lanham Act § 2(f), asserting acquired distinctiveness.
- The application was approved for publication, and competing manufacturers British Seagull Ltd. and Outboard Marine Corp. opposed registration; the Trademark Trial and Appeal Board (TTAB) consolidated the oppositions.
- Mercury had sold outboard engines for decades, introduced an all-black engine in 1962, and since 1964 had sold all Mercury outboards in black.
- Mercury presented substantial sales and advertising evidence, including advertising that emphasized “all black” motors.
- Other sellers in the market produced black or near-black outboard engines.
- The TTAB found black conferred marketplace advantages, including compatibility with a wider range of boat colors and making engines appear smaller than lighter colors.
- The TTAB sustained the oppositions, concluding black for outboard engines was de jure functional and that Mercury had not proved secondary meaning.
- Mercury appealed; the opposers cross-appealed certain evidentiary rulings.

## Issues

1. Whether the color black, as applied to outboard motors, is de jure functional and therefore unregistrable as a trademark.
2. Whether proof of acquired distinctiveness can overcome a finding of de jure functionality.
3. Whether an asserted limitation to a particular shade of black affects the registrability analysis.
4. Whether challenged TTAB evidentiary rulings required reversal.

## Decision

- The Federal Circuit affirmed the TTAB’s refusal to register the color black for outboard motors.
- The court held black was de jure functional because it provided non-reputation-related competitive advantages desired by consumers.
- The court held evidence of secondary meaning could not overcome de jure functionality.
- The court rejected Mercury’s attempt to recast the application as limited to a particular shade of black.
- The court affirmed the TTAB on the cross-appeal, finding no reversible evidentiary error.

## Legal Principles

- A product feature is unregistrable if exclusive rights would place competitors at a significant non-reputation-related disadvantage.
- Color can be de jure functional where it yields commercial advantages tied to consumer preference (including aesthetic advantages), even if it does not improve mechanical performance or reduce manufacturing cost.
- De jure functionality is an absolute bar to trademark registration; acquired distinctiveness cannot convert a functional feature into a protectable mark.
- A purported narrowing of a trademark application raised only in argument, rather than through a proper amendment, does not alter the registrability determination.

## Conclusion

The Federal Circuit held that black outboard motors confer competitive aesthetic advantages that competitors reasonably need to use, making the color de jure functional and unregistrable notwithstanding any consumer association with Mercury.


Brunswick Corp. v. British Seagull Ltd., 35 F.3d 1527 (Fed. Cir. 1994)