Richard Katz said Wednesday his client is "thrilled" to join Carolina.
A source confirmed Blackburn will sign a two-year deal with the team.
"Thanks for 8 great yrs @Giants," Blackburn tweeted Wednesday. "But it's time for the #nextChapter @Panthers. Excited for the new opportunity. Where all the Panther fans at."
Blackburn was the starting middle linebacker for the Giants last season, but the free agent had to find a new home after the team signed linebacker Dan Connor earlier this month.
The 6-foot-4 Blackburn will join Dave Gettleman, who left his post as director of pro personnel with the Giants this offseason to become the Panthers' general manager, in Carolina.
Blackburn started 19 games the past two seasons. He had 64 tackles, four forced fumbles and one interception during the 2012 season, his eighth with the Giants.
Blackburn is the second starting linebacker from last season not to return to the Giants. The team released Michael Boley in a cap-cutting move in February.
The Giants have Connor, Jacquian Williams, Keith Rivers, Mark Herzlich, Spencer Paysinger and Mathias Kiwanuka at linebacker. Kiwanuka, though, likely could move back to defensive end full time this coming season.
Information from The Associated Press was used in this report.