Adaptec was founded by Larry Boucher in 1981. At first, Adaptec focused on devices with SCSI interfaces.
On May 10, 2010, PMC-Sierra, Inc. and Adaptec, Inc. announced they had entered into a definitive agreement of PMC-Sierra acquiring Adaptec's channel storage business on May 8, 2010, which included Adaptec's RAID storage product line, the Adaptec brand, a global value added reseller customer base, board logistics capabilities, and SSD cache performance solutions. The transaction was expected to close in approximately 30 days, subject to customary closing conditions. Following the sale, Adaptec would retain its Aristos ASIC technology business, certain real estate assets, more than 200 patents, and approximately $400 million in cash and marketable securities.
On June 8, 2010, PMC-Sierra, Inc. and Adaptec, Inc. announced the completion of the acquisition. PMC-Sierra renamed the channel storage business "Adaptec by PMC".
Adaptec produced interface products involving SCSI, USB, IEEE 1394, iSCSI, Fibre Channel, and video. Adaptec once produced CD and DVD burning software under the brand names of Easy CD Creator and Toast, and network-attached storage devices such as the Snap Server product line.