Limitations that are common knowledge must be considered as part of the obviousness analysis even if the prior art does not disclose them for the specific purpose of the invention. Here, for example, the fact that press fitting as a means of attachment was common knowledge should have been considered as motivation to utilize press fitting for attaching weights to the shell of a golf club head. “[A]s part of the obviousness analysis, the prior art must be viewed in the context of what was generally known in the art at the time of the invention.”

Background / Facts: The patent on appeal here from rejection at the PTO during reexamination is directed to shifting the center of gravity of a golf club head by attaching removable weights. Shifting the center of gravity allows the user to change the behavior of the club and achieve certain results with respect to ball-flight when striking the ball. The limitations at issue relate to securing the weights via “press fitting.” Although press fitting techniques were known generally, the PTO determined that the disclosure of press fitting in the prior art did not render the claimed invention obvious because the prior art “fails to disclose or suggest press-fitting … at least one weight to the shell of a golf club head.”

Issue(s): Whether the PTO should have considered whether it would have been obvious to utilize press fitting even though the prior art did not disclose the use of press fitting for the specific purpose of the invention.

Holding(s): Yes. “There is no question here that press fitting as a means of attachment was common knowledge at the time of the invention. … Given that the common knowledge of press fitting was before the Board, it was error for the Board to fail to consider whether a person of ordinary skill in the art would be motivated to combine press fitting with the prior art (which, as the Board found, disclosed every other limitation of the [] patent) to arrive at the claimed invention. As we recently reaffirmed, the Supreme Court and this court require that, as part of the obviousness analysis, the prior art must be viewed in the context of what was generally known in the art at the time of the invention.”

Full Opinion