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Foiled by functionality - Expired patents undermine trademark eligibility
A ruling by the U.S. Court of Appeals for the Federal Circuit serves as an important reminder that trademark protection isn’t available for functional designs. It also demonstrates how some patents can contradict a would-be trademark holder’s claim that its design isn’t actually functional.
Hard matter
CeramTec GmbH manufactures artificial hip components made from a zirconia-toughened alumina (ZTA) ceramic that contains chromium oxide (chromia), among other things. CeramTec’s patent on the chemical composition credited the addition of chromia for increasing the hardness of ZTA ceramics. CeramTec has also applied for, and received, other patents that spoke to chromia’s impact on ZTA ceramic hardness.
The amount of chromia in a ceramic affects its coloring. CeramTec’s hip components used a percentage of chromia that made them pink.
CeramTec’s patent expired in January 2013. In April 2013, CeramTec was granted registration for two trademarks protecting the color pink used in ceramic hip components.
CoorsTek Bioceramics also manufactures a ZTA ceramic material for hip implants with a chromia percentage that makes the material pink. In 2014, it asked the Trademark Trial and Appeal Board (TTAB) to cancel CeramTec’s trademarks because the color pink that CeramTec claimed was functional.
The board sided with CoorsTek, finding that the color pink was functional as it relates to ceramic hip components, and canceled the marks. CeramTec appealed to the Federal Circuit.
In the pink
The functionality doctrine is intended to prevent a manufacturer from controlling a useful product feature. Patent law, not trademark law, is the avenue for granting a monopoly over new product designs or functions for a limited time. If a product’s functional features could be used as trademarks — which may be renewed in perpetuity — a manufacturer could obtain a permanent monopoly over such features regardless of whether they qualify for patents.
Four factors are evaluated in determining a trademark’s functionality:
- The existence of a utility patent covering the utilitarian advantages of the design,
- The availability to competitors of functionally equivalent designs,
- Facts indicating that the design results in a comparatively simple or cheap method of manufacturing the product, and
- Advertising materials where the designer touts the design’s utilitarian advantages.
On appeal, CeramTec challenged the TTAB’s analysis of the first three factors; the fourth was uncontested. The court found that substantial evidence supported the TTAB’s findings on the first, third and fourth factors. CeramTec admitted that its patent for the chemical composition attributed increased hardness levels of ZTA ceramics to the addition of chromia. This provided strong evidence that the resulting pink color was functional under the first factor.
The court also backed the TTAB’s determination that the third and fourth factors were neutral. It pointed to the lack of evidence that different-colored ceramic hip components worked equally as well as pink components. Moreover, the court found conflicting evidence on the relative costs of producing pink and nonpink components.
Be hip to this
Notably, the court rejected CeramTec’s assertion that a utility patent isn’t evidence of a design’s functionality unless the patent explicitly claims that feature. It also dismissed the argument that a utility patent is relevant to the inquiry only if the contested trademark is used for the goods described in the patent.
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