According to Ian Rapoport of the NFL Network, the Seahawks gave Lynch and the Raiders clearance to meet and Lynch told the Raiders he does intend to un-retire.
The Seahawks granted permission to the Raiders to speak with their retired running back.
There has been speculation for months now, but it appears as if Lynch is seriously thinking of coming out of retirement and getting back into the NFL.
ESPN's Adam Schefter believes that a deal "will eventually happen", but there are a number of hurdles that have to get cleared before you see Lynch holding a silver and black jersey.
Rapoport described the meeting as a "fact-finding mission" as the Raiders explore options at running back.
However, it could take some time for details to be worked out as Lynch's rights are still held by the Seahawks.
Considering the Raiders lost running back Latavius Murray to free agency, Lynch would be a logical fit for a Raiders offense that was among the best in the league a season ago. In his previous four seasons with Seattle, Lynch rushed for 1,200 yards and 10-plus touchdowns.
Lynch, 30, last played for the Seahawks in 2015 and announced his retirement on the day of Super Bowl 50. If he decides that he wants to play again, the first thing that he needs to do is apply for reinstatement.
He grew up in Oakland, so the Raiders leaving for a second time - they went to Los Angeles in 1982 before returning in 1995 - affected Henderson.