Former UFC middleweight Nate Marquardt has signed with Strikeforce. The move was announced by Ariel Helwani on tonight's episode of UFC Tonight on Fuel. Fuel TV's twitter account verified the news as well:
Marquardt, who went 10-4 in his middleweight run in the UFC, was released by the promotion shortly before UFC on Versus 4, where he was going to make his welterweight debut against Rick Story. Marquardt had issues with his testosterone replacement therapy and couldn't get his levels under the Pennsyvlania Athletic Commission's set limit, which forced Dana White to remove him from the fight (and the company) and replace him with Charlie Brenneman.
Nate had signed with BAMMA a few months ago, but card delays led to him never fighting for the organization. He was released from his contract with them a few weeks ago, and will now join Strikeforce. It is unclear at this point if he will be competing at 185 or 170.
Update: Ariel said that Nate will be staying at welterweight.