A source told ESPN's Field Yates that Irvin's four-year deal with the Raiders includes $12.5 million fully guaranteed (all in 2016) and is worth a maximum of $37 million.
One connection Irvin has to Oakland is defensive coordinator Ken Norton Jr., who served as the Seahawks' linebackers coach for the first three years of Irvin's career and helped Irvin transition from his role in college as a true defensive end.
Irvin, 28, played a versatile role in Pete Carroll's defense, lining up at strongside linebacker in the base defense and moving to defensive end in the Seahawks' sub packages.
Irvin (6-foot-3, 260 pounds) has 22 sacks in his four-year career, with 37 starts in 58 games. Last season, he had 5½ sacks and 38 tackles. A special athlete, Irvin has scheme versatility, with the ability to play standing up as a linebacker or with his hand on the ground as a defensive end. He was the 15th overall pick in the 2012 draft.
ESPN Seahawks reporter Sheil Kapadia contributed to this report.