Allen died in Seattle of complications from non-Hodgkin's lymphoma, his family and his company, Vulcan Inc., announced.
"My brother was a remarkable individual on every level," said his sister, Jody Allen. "While most knew Paul Allen as a technologist and philanthropist, for us he was a much loved brother and uncle, and an exceptional friend."
With his sister Jody in 1986, he founded Vulcan, the investment firm that oversees his business and philanthropic efforts. He founded the Allen Institute for Brain Science and the aerospace firm Stratolaunch, which has built a colossal airplane designed to launch satellites into orbit. He has also backed research into nuclear-fusion power.
Vulcan Inc's statement on Paul Allen is available here.
Statement from Microsoft CEO Satya Nadella on the passing of Paul Allen: pic.twitter.com/1iLDLenLKz— Microsoft (@Microsoft) October 15, 2018
Allen and Bill Gates founded Microsoft Corp. in 1975. The company'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.
Paul was a truly wonderful, bright and inspiring person—- and a great friend. I will miss him https://t.co/HYhtgZGo8C— Steve Ballmer (@Steven_Ballmer) October 15, 2018
Over the course of the several decades, Allen gave more than $2 billion to a wide range of interests, including ocean health, homelessness and advancing scientific research.
Allen later joined the list of America's wealthiest people who pledged to give away the bulk of their fortunes to charity. In 2010, he publicly pledged to give away the majority of his fortune, saying he believed "those fortunate to achieve great wealth should put it to work for the good of humanity."
We miss you.— Trail Blazers (@trailblazers) October 15, 2018
We thank you.
We love you. pic.twitter.com/rxkn1IjJ0R
When he released his 2011 memoir, "Idea Man," he allowed 60 Minutes inside his home on Lake Washington, across the water from Seattle, revealing collections that ranged from the guitar Jimi Hendrix played at Woodstock to vintage war planes and a 300-foot yacht with its own submarine.
Allen served as Microsoft's executive vice president of research and new product development until 1983, when he resigned after being diagnosed with cancer.
"To be 30 years old and have that kind of shock - to face your mortality - really makes you feel like you should do some of the things that you haven't done yet," Allen said in a 2000 book, "Inside Out: Microsoft in Our Own Words," published to celebrate 25 years of Microsoft.
Our industry has lost a pioneer and our world has lost a force for good. We send our deepest condolences to Paul’s friends, the Allen family and everyone at Microsoft.— Tim Cook (@tim_cook) October 15, 2018
The Associated Press contributed to this report.
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