The Court of Appeals for the Federal Circuit (CAFC) overruled a long standing test on Tuesday (21 May) when assessing non obviousness in design patent cases, supporting the more flexible approach used for utility patents.

The test – known as the Rosen-Durling test – had been used consistently for 30 years.

The LKQ v General Motors dispute saw auto part makers LKQ Corporation and Keystone Automotive Industries, collectively known as ‘LKQ Corp’, attempt to invalidate a design patent owned by General Motors directed at the front fender of a car.

The Patent Trial and Appeal Board (PTAB) of the US Patent and Trademark Office initially shot down LKQ’s patent validity challenge, but LKQ appealed and now CAFC has ruled that the test used by the PTAB when reaching its decision was not flexible enough in its present form.

CAFC said that the Supreme Court had recently addressed the standards for assessing non obviousness in KSR v Telefax, establishing that flexibility is required when determining the obviousness of utility patents.

It said it was adopting an approach “consistent with Congress’s statutory scheme for design patents, which provides that the same conditions for patentability that apply to utility patents apply to design patents, as well as Supreme Court precedent which suggests a more flexible approach than the Rosen-Durling test for determining nonobviousness”.

Scott Hejny, principal at McKool Smith, said that the CAFC’s en banc re-definition of the test for design patents in LKQ was “probably the right decision since the Supreme Court clearly criticised bright line tests like Rosen-Durling in KSR".

He added that the Federal Circuit seemed to focus on the Supreme Court’s guidance in KSR, which noted that “rigid preventative rules that deny factfinders recourse to common sense“ are improper under US design law.

GM owned the design patent for a car front fender, but LKQ challenged the validity of the patent at PTAB, petitioning it to find the design unpatentable for obviousness because of two previous design references.

A design patent protects a “new, original and ornamental design for an article of manufacture”. It can be declared unpatentable if the prior art made the claimed-for design obvious before the effective filing date.

The PTAB ruled that LKQ had not established by a preponderance of the evidence that another design had anticipated the claim of the patent.

LKQ appealed, and a panel of CAFC affirmed the board decision. However, in June last year the court granted rehearing en banc and vacated the panel opinion.

After this week’s decision, the case has now been sent back to PTAB.

Commenting on the implications of the case, Hejny said the less rigid test set out in this ruling “won’t be viewed favourably by design patentees, because design patents will now be harder to obtain and much easier to challenge”.

He added: “On the whole, however, the old Rosen-Durling test and its stringent requirements of identifying a primary reference that is ‘basically the same as’ the challenged design, along with a very closely related secondary reference, seems contrary to KSR guidelines.”

Amici curiae speaking out against discarding the test included influential bodies like the International Trademark Association, which said elimination or substantial modification of the test would create uncertainty and “upset the carefully crafted, long-established balance between design patent and trade dress protection, to the detriment of both intellectual property owners and consumers alike”.

The automotive industry had also come out in defence of the test including Ford, Hyundai and Kia.