Williams' status was uncertain after he missed all of the team's spring practices while still recuperating from back surgery in October. Though the Bills medical staff was monitoring his progress, Williams did not report to the team's facility until the start of a mandatory minicamp last month.
The Bills announced the move on Tuesday evening.
The Bills were counting on Williams to fill a starting spot when they signed the free agent to a four-year contract in March 2014. He was limited to playing three games before being placed on season-ending injured reserve.
The seventh-year player was scheduled to make a base salary of $1.875 million this season.
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