Thompkins, 27, signed with the Patriots as an undrafted free agent out of Cincinnati back in 2013. He was able to make the Patriots 53-man roster coming out of the preseason, but released a months into of the 2014 regular season.
The Raiders wound up claiming Thompkins off of waivers back in October of last year, but he was unfortunately among their final roster cuts from a month ago.
New England elected to bring him back a few weeks ago.
In 2014, Thompkins appeared in 14 games and caught 21 passes for 262 yards receiving and no touchdowns.