A native Iranian, Yassaie came to the UK in 1976 and went to Birmingham University. He worked for Inmos in DSP and digital video development and for STMicroelectronics which bought Inmos.
He joined Imagination in 1992 as Technical Director when the company went under its original name VideoLogic.
Yassaie became CEO in 1998 and changed the name to Imagination Technologies in 1999, refocussing the company on IP licensing.
He expanded the company through a series of acquisitions: Ensigma in 2000, Cross Products in 2001, HelloSoft and Caustic Graphics in 2010, and MIPS this year.
In 2001 Yassaie set up PURE the digital radio company as a subsidiary of Imagination.
Intel owns 16.2% of Imagination, Apple owns 9.5% and Renesas owns 3.5%.
Yassaie drove Imagination's strategies in 3D graphics, digital video and display, programmable communications and embedded processing.
"In underlying technologies the UK is the leading country in terms of providing intellectual property and technology," Yassaie told the BBC this weekend.
He's the first semiconductor CEO to be knighted since Sir Robin Saxby of ARM and, like Saxby, Yassaie is a good bloke, good fun. His employees have a real affection for him which is always a good sign.