The first major free agent signing by general manager Ryan Pace, McPhee had trouble staying healthy in three seasons with the Bears. He had 90 tackles and 14 sacks in 36 games for Chicago after playing his first four years with the Baltimore Ravens.
McPhee missed the first six games in 2016 following surgery on his left knee and had arthroscopic surgery on his right knee in July. He also sat out three games late last season because of a shoulder ailment and finished the season on injured reserve.
A broken arm limited Demps, who signed with Chicago in March, to three games.
The Bears announced the moves on Monday.
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