The NFL is reviewing an alleged autograph interaction between two referees and Tampa Bay Buccaneers wide receiver Mike Evans, a league source told Yahoo Sports. The exchange was captured on video by a Carolina Panthers beat writer and posted on Twitter following the game.

In the two interactions on a pair of separate videos, referees Tripp Sutter and Jeff Lamberth can be seen handing Evans a piece of paper and a writing utensil, at which point each stands by individually as Evans appears to write something down before handing the paper back to them. It was filmed by Panthers beat writer Sheena Quick, who posted each to her Twitter account following the Panthers’ 21-3 win over the Buccaneers.

The collective bargaining agreement has a provision between the NFL and NFL Referees Association that regulates the conduct of officials and prohibits them from directly “ask[ing] players, coaches or any other team personnel for autographs or memorabilia.” However, officials can seek autographs with direct requests through the league’s officiating department.