Rugby league agent Andy Clarke is under investigation by the RFL for his behaviour in the Denny Solomona episode.
Solomona is believed to be trying to enact a move to rugby union club Sale Sharks despite being under contract with Castleford. The Tigers have repeatedly stated that the winger is not for sale.
Love Rugby League understands Clarke, one of the top agents in Super League, is being investigated for his behaviour and conduct around transfer dealings.
Clarke is the brother of former Wigan player and Sky pundit Phil Clarke and represents Solomona.
The RFL is supporting Castleford in this case.
Solomona joined the Tigers at the end of 2014 on a two-year deal. He signed an extension at the end of 2015 tieing him to the club until the end of 2018.
Solomona enjoyed an outstanding 2016 season, scoring 40 tries and was shortlisted for the Man of Steel award.