SEATTLE (CBSLA/AP) — Paul Allen, the billionaire technology pioneer and philanthropist who co-founded Microsoft with Bill Gates, has died just weeks after announcing a renewed battle with cancer, according to his company Vulcan Inc.

Allen, who also owned the NFL’s Seattle Seahawks, tweeted Oct. 1 that the non-Hodgkin’s lymphoma he was treated for in 2009 had returned, and that he planned to fight it aggressively.

The 65-year-old had intended to stay involved with his Vulcan real estate company, the Allen Institutes, the Seahawks and the Portland Trail Blazers, but had handed off operations to his leadership teams while undergoing treatment.

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Allen and Gates founded Microsoft Corp. in 1975. Microsoft’s big break came in 1980, when IBM Corp. decided to move into personal computers. IBM asked Microsoft to provide the operating system. The decision thrust Microsoft onto the throne of technology and the two Seattle-natives became billionaires. Both later dedicated themselves to philanthropy.

Over the course of several decades, Allen gave more than $2 billion to a wide range of interests, including ocean health, homelessness and advancing scientific research.

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