Paul Allen, the owner of the Seattle Seahawks and the Portland Trail Blazers, died of cancer Monday at age 65. His family announced the news, saying that while “most knew Paul Allen as a technologist and philanthropist, for us he was a much loved brother and uncle, and an exceptional friend.”

A native of Seattle, Allen made his fortune by co-founding Microsoft with Bill Gates, and he became an owner of a major professional sports team when he purchased the Trail Blazers in 1988. His 1996 acquisition of the Seahawks was considered pivotal in preventing the franchise from relocating to California.

At the start of month, Allen announced that the non-Hodgkin’s lymphoma for which he was treated in 2009 had returned. He said then that he planned on “fighting this aggressively” and that his doctors were “optimistic” that he would “see good results from the latest therapies,” but according to his family, he lost that battle Monday afternoon.

“Paul Allen was the ultimate trail blazer — in business, philanthropy and in sports,” NBA Commissioner Adam Silver said in a statement. “As one of the longest-tenured owners in the NBA, Paul brought a sense of discovery and vision to every league matter large and small. He was generous with his time on committee work, and his expertise helped lay the foundation for the league’s growth internationally and our embrace of new technologies. He was a valued voice who challenged assumptions and conventional wisdom and one we will deeply miss as we start a new season without him. Our condolences go to his family, friends and the entire Trail Blazers organization.”

Allen’s death came on the eve of an NFL owners’ meeting scheduled for Tuesday and Wednesday in New York. He was not visible in league operations, very rarely attending owners’ meetings. But his presence was felt within the sport, NFL Commissioner Roger Goodell said.

“Paul Allen was the driving force behind keeping the NFL in the Pacific Northwest,” Goodell said in a statement. “His vision led to the construction of CenturyLink Field and the building of a team that played in three Super Bowls, winning the championship in Super Bowl XLVIII. The raising of the ‘12th Man’ flag at the start of every Seahawks home game was Paul’s tribute to the extraordinary fan base in the Seattle community. His passion for the game, combined with his quiet determination, led to a model organization on and off the field.

“He worked tirelessly alongside our medical advisers to identify new ways to make the game safer and protect our players from unnecessary risk,” Goodell continued. “I personally valued Paul’s advice on subjects ranging from collective bargaining to bringing technology to our game. Our league is better for Paul Allen having been a part of it and the entire NFL sends its deepest condolences to Paul’s family and to the Seahawks organization.”

Allen was also a part owner of MLS’s Seattle Sounders, and he had a wide range of philanthropic interests. He was generally regarded as a relatively hands-off owner of the Seahawks and Trail Blazers, which benefited from the stability he brought to the organizations.

Allen did make an appearance in the Seahawks’ locker room and spoke to reporters after the team secured its first Super Bowl appearance by beating the Carolina Panthers in Seattle in the NFC title game in January 2006.

“You hear about everybody wearing blue and the '12th-Man' flag being on top of the Space Needle and so many people saying, 'Now, Paul, you just don't understand how crazy people are in Seattle about this game,' " Allen said that day. “For me, I seem like a pretty mild-mannered guy, but inside I get like, 'Let's win this game. Let's please win this game.' So it's just very rewarding.”

Allen, then listed at the world’s seventh-richest man by Forbes, said that day he’d gotten emotional before that game when he’d raised the 12th Man flag at one end of the stadium. It was the first time he’d done that, Allen said, and he said he’d been thinking about his late father Kenneth, who had taken him to University of Washington football games.

“That did choke me up a little bit, just thinking I wish he would have been able to come to [that] game,” Allen said.

Seahawks Coach Pete Carroll said on Twitter that he was “deeply saddened” by Allen’s passing, and that he would “miss him greatly.” Carroll added, “His gracious leadership and tremendous inspiration will never be forgotten. The world is a better place because of Paul’s passion, commitment, and selflessness. His legacy will live on forever.”

Seattle defensive lineman Frank Clark said on Twitter that he hoped his team sent Allen out “with high praises with our victory yesterday in London,” in a dominating win over the Raiders. “You with the most high now,” he added, “no more pain required.”

“Rest In Peace to this Beautiful mind,” Blazers player Evan Turner, whose team begins its regular season on Thursday, said on Instagram. “You’ll be forever remembered and missed. God bless you, Paul.”

“RIP Paul. You were a good man and will be missed,” Dallas Mavericks owner Mark Cuban said on Twitter. “Rock and Roll Heaven just got a lot better.”

“Paul’s life was diverse and lived with gusto,” Bill Hilf, the CEO of Vulcan Inc., which managed Allen’s fortune, said in a statement. “It reflected his myriad interests in technology, music and the arts, biosciences and artificial intelligence, conservation and in the power of shared experience — in a stadium or a neighborhood — to transform individual lives and whole communities.”

Hilf said there are “no changes imminent” for the teams owned by Allen but did not provide further specifics.

“Paul thoughtfully addressed how the many institutions he founded and supported would continue after he was no longer able to lead them,” Hilf said. “This isn’t the time to deal in those specifics as we focus on Paul’s family. We will continue to work on furthering Paul’s mission and the projects he entrusted to us. There are no changes imminent for Vulcan, the teams, the research institutes or museums.”

After having made the playoffs just four times in their first 20 years of existence before being purchased by Allen in 1996, the Seahawks went to the postseason 12 times over the next 21 years, including three appearances in the Super Bowl and the franchise’s one championship in 2014. The Blazers have missed the playoffs just seven times in the past three decades, and they twice reached the NBA Finals in that span.

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