The contract is the richest for a rookie non-quarterback in NFL history, The Associated Press reports, and has a maximum value of $60 million, according to the league source.
Curry, the No. 4 overall pick in the April draft, made a surprise appearance at Saturday's practice, sprinting onto the field almost 30 minutes into the session to boisterous applause from Seahawks fans in attendance.
"I am just as excited to be out here and just to see the emotion from the fans and get back with my team is just an amazing feeling," said Curry, who played collegiately at Wake Forest.
Seahawks coach Jim Mora said Curry has a steep learning curve after missing 12 practices over eight days of training camp. That was evident the moment the Seahawks thrust Curry into one-on-one drills, without the linebacker having done so much as stretch or warm-up.
On his first play, Curry was matched up against tight end Cameron Morrah, who burned him on a square-in route. One fan sarcastically yelled out, "Welcome to the NFL."
Curry spent the afternoon practicing with Seattle's No. 2 defense, but Mora made it clear that the rookie will start at strong-side linebacker.
"He wasn't in there with the first group just because he's got so much catching up to do," Mora said. "I don't know at what point we'll make the switch and he'll start running out there with the first defense, but I think it will be pretty soon."
Although he worked out and studied his playbook in nearby Bellevue during the holdout, Curry said he grew anxious and eventually told his agents to speed up the contract negotiations.
Fellow rookie Deon Butler filled in Curry on practice matters during the holdout, and Lofa Tatupu also visited, giving his fellow linebacker a mini-walkthrough of what the defense was doing. But Tatupu believed Curry would quickly acclimate himself with the Seahawks' strategy during camp.
"Linebacker, it's not like it's rocket science," Tatupu said with a laugh. "Just hit the man with the ball."
Mora credited Seahawks general manager Tim Ruskell for working the phones with Curry's representatives late into Friday night.
"This is probably the longest contract we'll ever do, in terms of pages and volume and little nuances to the deal," Ruskell said.
Notes: Mora said he believed the Seahawks "dodged a bullet" with the injury to Chris Spencer. The center was carted off the field Friday with an ankle injury, but he was walking around Saturday. ... Walter Jones also didn't practice because of a back injury, and Mora said the veteran offense tackle wouldn't play in the team's first preseason game Aug. 22. The coach was optimistic that Jones would be involved in practice soon. ... Also not practicing Saturday was CB Marcus Trufant (back), DL Cory Redding (soreness), DE Michael Bennett (knee) and OG Grey Ruegamer (elbow). ... To make roster room for Curry, the Seahawks waived WR Billy McMullen.
The Associated Press contributed to this report.