Prosecution History May Support a Motivation to Combine

Elekta Limited v. Zap Surgical Systems, Inc.

Before: Reyna, Stoll, and Stark. Appeal from the Patent Trial and Appeal Board.

Summary: Patentee’s failure during prosecution to distinguish relevant art provided support for motivation to combine.

Elekta owns U.S. Patent No. 7,295,648 (the ’648 patent) directed towards a radiation therapy device. The device is rotatable, allowing for the delivery of radiation to different target areas. ZAP filed an IPR petition, which the PTAB instituted. In its Final Written Decision, the PTAB found all challenged claims to be obvious. Specifically, the PTAB found that the claims were obvious over the combination of (1) a rotatable radiation imagery device and (2) a radiation therapy device.

On appeal, Elekta argued that the PTAB’s decision was not supported by substantial evidence since imaging devices do not contemplate the heavy components of therapy devices, and that the added weight of these components would cause the device to lack the precision required for radiation therapy.

The Federal Circuit disagreed with Elekta. The Federal Circuit held that the PTAB’s finding of a motivation to combine was supported by substantial evidence, “including the prosecution history of the ’648 patent,” the teachings in the prior art, and expert testimony submitted by ZAP. The Federal Circuit explained that during prosecution of the ’648 patent, “patents directed to imaging devices were cited, and were not distinguished based on an argument that imaging devices were not relevant art.” Further, the prior art taught that combining an imaging system with a radiation source was preferable, and ZAP’s expert opined that a person of ordinary skill in the art would have been motivated to make the combination because it would “eliminat[e] the need to move a patient” and would “reduce the patient’s radiation exposure.”  Therefore, the Federal Circuit found that substantial evidence supported a motivation to combine.

Elekta also argued on appeal that the PTAB erred by failing to expressly articulate any findings on reasonable expectation of success, and that no substantial evidence supported the determination. The Federal Circuit again disagreed with Elekta. The Federal Circuit stated that, unlike a motivation to combine determination, which requires an explicit analysis, “a finding of reasonable expectation of success can be implicit.” The Federal Circuit explained that it could “reasonably discern” an implicit finding by the PTAB on reasonable expectation of success based on the PTAB’s analysis of “other, intertwined arguments [such as] a motivation to combine.” The Federal Circuit held that the PTAB’s decision was supported by substantial evidence because the arguments and evidence of reasonable expectation of success were the same for motivation to combine in this case.  The Federal Circuit therefore affirmed the PTAB’s obviousness determination.

Editor: Paul Stewart