Prosinski, 30, is a former fourth-round pick of the Jaguars back in 2011. He spent three years in Jacksonville before he was waived at the start of the 2014 season with an injury settlement.
The Eagles later signed him to a contract, but he was cut loose the following year and later caught on with the Bears soon after. Chicago brought Prosinski back on a one-year, $855,000 contract this past March.
In 2016, Prosinski appeared in all 16 games for the Bears last year and recorded 25 tackles, no interceptions and a pass defense while contributing on special teams.