Second-rowers Heighington and Mataka will be at the club now until the end of the 2008 season. Trimarchi has signed on to the end of the 2009 season.
Heighington has played 62 games for the Wests Tigers since making his first grade debut against St George Illawarra at Telstra Stadium in round one of the 2003 season.
Heighington has also been a tremendous ambassador for the club off the field, winning the inaugural Wests Tigers community award in 2006.
Trimarchi is one of the club