Seahawks, Trail Blazers owner Paul Allen dies at 65

Allen had announced earlier this month that the disease, which he had been treated for in 2009, had returned.

Allen's sister, Jody Allen, wrote in a statement: "My brother was a remarkable individual on every level. While most knew Paul Allen as a technologist and philanthropist, for us he was a much loved brother and uncle, and an exceptional friend."

Allen, who co-founded Microsoft with his childhood friend Bill Gates, had owned the Seahawks since 1997 and the Blazers since 1988. He's also the co-owner of the MLS' Seattle Sounders FC.