"We have a loyal, passionate and growing fan-base. We have built some exceptional public and private sector partnerships, and we have a playing squad that has made significant improvement this year, with an ideal blend of local young talent and experience," he said.
"When Steve proposed me taking an ownership stake, I didn't hesitate. I believe we have huge potential and I am excited about playing a part in the realisation of that potential."
Rule previously worked as chief executive at Hull FC.