The news was first reported by The Seattle Times.
Sherman told ESPN's Josina Anderson earlier this week that he planned on speaking on the phone with coach Pete Carroll and general manager John Schneider about his future.
Sherman's future with the Seahawks has been in question dating to last offseason, when the team publicly acknowledged that it was open to trading him.
He is coming off a ruptured right Achilles that ended his 2017 season in November and recently had a cleanup procedure on the same part of his other foot. Sherman said last month that he expected to resume running around mid-April or early May. He also told reporters that he has been serving as his own agent for at least the past year.
Sherman, who will turn 30 at the end of March, is entering the final year of a four-year, $56 million extension that he signed in 2014 after the Seahawks won Super Bowl XLVIII. He is scheduled to count $13.2 million against the 2018 salary cap.
Seattle would save $11 million in cash and cap space by releasing or trading Sherman before June 1.
Sherman has played his entire seven-year career in Seattle, compiling 32 interceptions.
The developments with Sherman come two days after the Seahawks agreed to a trade with the Eagles that will send defensive lineman Michael Bennett and a seventh-round pick to Philadelphia in exchange for a fifth-round pick and wide receiver Marcus Johnson, according to ESPN's Adam Schefter.
While Sherman's future in Seattle is cloudy and Bennett has been traded, another Seahawks defensive stalwart isn't likely to be going anywhere, a source told ESPN.
Safety Earl Thomas is expected to return to Seattle for the 2018 season, the source said. Thomas' name had come up in trade discussions, but it was Seattle listening to trade proposals, not the Seahawks shopping him. Thomas is much more likely to receive an extension than he is to be traded this offseason, the source said.
Information from ESPN Seahawks reporter Brady Henderson was used in this report.