What is the significance of the CTS Corp. v. Piher Int’l Corp. case in pre-AIA patent law?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

The case of CTS Corp. v. Piher Int’l Corp., 593 F.2d 777, 201 USPQ 649 (7th Cir. 1979) is significant in pre-AIA patent law for its interpretation of the on-sale bar’s application to foreign activities. The MPEP 2133.03(d) cites this case to illustrate an important principle:

“The same rationale applies to an offer by a foreign manufacturer which is communicated to a prospective purchaser in the United States prior to the critical date.”

Key points from this case:

• It established that offers from foreign manufacturers can trigger the on-sale bar if communicated to U.S. buyers.
• The location of the manufacturer is less important than the communication of the offer to a U.S. entity.
• It expanded the understanding of what constitutes “in this country” for the purposes of the on-sale bar.

This case is crucial for understanding how pre-AIA law treated foreign sales activities and their potential to create prior art under 35 U.S.C. 102(b). It highlights the importance of considering international business communications in patent law analysis.