Nkemdiche was signed by the Seahawks on Tuesday, John Boyle of the Seahawks' official site reports.
Nkemdiche was released in the final wave of camp cuts by Seattle, though he later landed back on the team's practice squad. He was elevated to the active roster for the last two weeks, recording nine total tackles while also shouldering a fairly heavy load along the defensive line. Nkemdiche should continue to serve as a rotational player for the remainder of the season.