Paul Allen died on Oct. 15 at the age of 65, Vulcan Inc. stated. Earlier this month, Allen said the non-Hodgkin's lymphoma he was treated for in 2009 had returned.
He co-founded Microsoft with his childhood friend Bill Gates in 1975. Their big break came in 1980, when IBM Corp. decided to move into personal computers.
After becoming billionaires, both later dedicated themselves to philanthropy. Allen gave over $2 billion to improving ocean health, homelessness, and advancing scientific research.