Simonson has played in 18 career games and started one game for the Panthers in 2016. He spent all of last season on injured reserve in Carolina due to a back injury.
Simonson signed with the Raiders as an undrafted free agent out of Assumption College in 2014. He appeared in four games for Oakland that season before being waived the following summer. He bounced between the Panthers practice squad and active roster for much of the next two seasons, appearing in 14 games.
The Giants waived defensive back Aaron Davis with an injury designation to clear a spot for Simonson on their roster.