Microsoft co-founder Paul Allen passed away today at the age of 65 after revealing earlier this month that he was being treated for non-Hodgkin lymphoma.

The tech pioneer and incredible investor and philanthropist is being remembered across the world this evening. The announcement was made by Allen’s company Vulcan Inc.

Allen cofounded Microsoft in 1975 with Bill Gates. Allen left the company just 8 years later while being treated for Hodgkin’s lymphoma, though he remained a board member through 2000. In 2009, Allen began treatment for non-Hodgkin lymphoma, and it subsequently went into remission. Just two weeks ago, however, Allen said he was again undergoing treatment for the cancer.

Apple CEO Tim Cook shared his condolences on Twitter this evening, saying the tech industry “lost a pioneer” while the world lost a “force for good.”

Allen’s sister, Jody Allen, said his family remembers him as a “much-loved brother and uncle, and an exceptional friend.”

Allen was also the owner of the Portland Trail Blazers, with NBA Commissioner Adam Silver this evening crediting him with helping “lay the foundation for the league’s growth internationally and our embrace new technologies.”

Paul’s family and friends were blessed to experience his wit, warmth, his generosity and deep concern. For all the demands on his schedule, there was always time for family and friends. At this time of loss and grief for us – and so many others – we are profoundly grateful for the care and concern he demonstrated every day.”

Likewise, Allen owned the Seattle Seahawks, and NFL Commissioner Roger Goodell says he pushed for making the games safer and preventing players from unnecessary risk (via ESPN):

Current Microsoft CEO Satya Nadella said in a statement that Allen’s contributions to society and Microsoft are “indispensable.”

According to his website, Allen’s “philanthropic contributions exceed $2 billion,” ranging from environmental causes, to homelessness, machine learning, and much more.