A group of Rangers supporters will write to the 50 major shareholders in Rangers International Football Club to urge them to take into account the views of fans and back their campaign for boardroom change.

The Sons of Struth have held a series of protests against the directors, culminating in a red card display at Ibrox on Saturday that involved a significant majority of the home crowd.

A group of Rangers fans will also meet Laxey Partners - the largest single shareholder - in London today. Laxey previously indicated they would take into account the views of supporters when voting at the annual meeting in nine days' time, but have since said they will vote to re-elect the current directors. All of the major fan groups have campaigned for change, including the Rangers Supporters Trust, the Rangers Supporters Association and the Rangers Supporters Assembly, with Sons of Struth taking an increasing role. The red card display on Saturday was the most prominent and heavily supported protest so far.

"We're saying to the major investors 'Don't turn your backs on the fans'," said Craig Houston, a spokesman for Sons of Struth. "We're working with all the organised fan groups, and the response we had from the fans in the stands shows without doubt that the board does not enjoy popular support. To protect their investment and for the club to flourish, the investors have to stand with the fans. It's time for change."

Fifty shareholders in RIFC own around 90% of the shares and a simple majority of those who vote at the annual meeting on December 19 at Ibrox will determine which directors - David Somers, the chairman, Graham Wallace, the chief executive, Brian Stockbridge, the finance director, Norman Crighton and James Easdale - remain in place and which of the nominees - Paul Murray, Malcolm Murray, Alex Wilson and Scott Murdoch - join the board.

The Sons of Struth will urge the shareholders to "stand with the vast and overwhelming majority of the fans and demand change on the Board at Ibrox".