Linear Technology Corp. v. Micrel, Inc.

On November 18, 1986, Linear Technology Corp. (LTC) (plaintiff) applied for a patent on an invention involving switching regulator circuitry. The functioning version of the invention was the LT1070 silicon chip. Micrel, Inc. (defendant), a competitor of LTC, later began selling similar chips. LTC brought a patent-infringement suit in federal district court. Micrel contended that LTC had offered the LT1070 for sale more than a year before the patent’s filing date, thus invalidating the patent on the basis of the on-sale bar. The court found that LTC had triggered the on-sale bar by four activities occurring before the critical date: (1) solicitation of pricing information from distributors and sales representatives, (2) publication of preliminary data sheets and promotional information, (3) sales-related communications from LTC to its sales force and from sales representatives to customers, and (4) sales representatives’ requests for LT1070 samples to give to customers. The court also found that LTC had sold the LT1070 when it entered purchase orders from four European distributors into its system before the critical date. However, this was accompanied by communications to the distributors stating that the orders had been received but not booked. There was no testimony as to how the European distributors interpreted these communications. The court ruled in favor of Micrel. LTC appealed to the United States Court of Appeals for the Federal Circuit.