Paul Allen, the co-founder of software giant Microsoft, has died at the age of 65 from complications caused by non-Hodgkin's lymphoma.
Allen's investment firm, Vulcan Inc, announced his death in Seattle on Monday afternoon, just two weeks after he had revealed that the non-Hodgkin's lymphoma that he was treated for in 2009 had returned.
"A lot has happened in medicine since I overcame this disease in 2009," Allen wrote. "My doctors are optimistic that I will see good results from the latest therapies, as am I."
Allen, a native of Seattle, went to high school with Bill Gates, and the two kept in touch at University. When Allen dropped out in 1975 to start a company to develop software for the MITS Altair 8800, he convinced Gates to join him.
Allen was first diagnosed with Hodgkins lymphoma in 1982 and resigned from Microsoft the following year
That company was Micro-Soft, which shed its hyphen the following year and, in 1980, Microsoft was chosen by IBM to develop DOS for its new PC. Allen was instrumental in putting together a deal to buy an operating system from a programmer in Seattle, which later became MS-DOS, the operating system that guided the IBM personal computer, introduced in 1981.
Allen was first diagnosed with Hodgkins lymphoma in 1982 and resigned from Microsoft the following year. He retained his share of ownership and became a billionaire when the company went public in 1986.
"From our early days together at Lakeside School, through our partnership in the creation of Microsoft, to some of our joint philanthropic projects over the years, Paul was a true partner and dear friend," said Gates.
A lot has happened in medicine since I overcame this disease in 2009. My doctors are optimistic that I will see good results from the latest therapies, as am I
"He deserved much more time, but his contributions to the world of technology and philanthropy will live on for generations to come. I will miss him tremendously."
Current Microsoft CEO Satya Nadella said Allen had made "indispensable" contributions to Microsoft and the technology industry.
"As co-founder of Microsoft, in his own quiet and persistent way, he created magical products, experiences and institutions, and in doing so, he changed the world," Nadella said.
And former Microsoft CEO Steve Ballmer called Allen a "truly wonderful, bright and inspiring person."
Paul was a true partner and dear friend
There have also been outpourings from the wider technology community, with Apple CEO Tim Cook calling Allen "a pioneer and a force for good", and Amazon CEO Jeff Bezos praising his "relentless" push forward in technology.
Allen, also an avid sports fan and owner of both the Portland Trail Blazers basketball team and Seattle Hawks NFL team, is estimated to have donated more than $2 billion to good causes throughout his life, including science, education and wildlife conservation.
In 2010 he pledged to give the majority of his fortune to charity after his death.
Dubbed Barnard's star B, newly discovered planet is believed to be rocky
Also, what's a USB stick?
Gravitational waves become extremely weak by the time they reach the Earth and require highly sensitive equipment for detection
The reactor topped out at 100 million° C