Microsoft co-founder Paul Allen died last week at age 65. Photo / Getty Images
Paul Allen's death certificate has been released, revealing that septic shock was the immediate cause of his death on Monday at age 65.
The State of Washington Department of Health death certificate was filed on Friday in King County, revealing that Allen suffered from septic shock for several days before he died, TMZ reported.
Septic shock is a widespread infection that can lead to extremely low blood pressure and multiple organ failure.
The death certificate also notes that Allen had been suffering from non-Hodgkin's lymphoma for several years, as was widely known, and immunosuppression, the Daily Mail reports.
Cardiomyopathy and acute kidney injury were also listed as conditions contributing to death.
The Microsoft founder's death came just two weeks after it was revealed that he was battling non-Hodgkin's lymphoma for the third time.
It was complications from that cancer which led to his death according to his family.
"While most knew Paul Allen as a technologist and philanthropist, for us he was a much-loved brother and uncle, and an exceptional friend. Paul's family and friends were blessed to experience his wit, warmth, his generosity and deep concern," said his sister Jody in a statement.
"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."
On the day of his death, Forbes revealed that Allen had donated $95 million in just the past year.
Allen struck gold when he founded Microsoft with Bill Gates, his childhood friend who he convinced to drop out of Harvard to start the company.
Allen had a net worth of approximately $20.3 billion and a real estate portfolio that is worth well over one-billion dollars.
He also owned the Seattle Seahawks and Portland Trailblazers.
It was earlier this month that he announced the return of his cancer in a post he shared on social media.
"Some personal news: Recently, I learned the non-Hodgkin's lymphoma I battled in 2009 has returned. I've begun treatment & my doctors are optimistic that I will see a good result," wrote Allen.
"Appreciate the support I've received & count on it as I fight this challenge."
He refused to let the diagnosis slow him down in any way though, and vowed to continue working despite his weakened state of health.
"I will continue to stay involved with Vulcan, the Allen Institutes, the Seahawks and Trail Blazers, as I have in the past. I have confidence in the leadership teams to manage their ongoing operations during my treatment," said Allen at the time.
"I am very grateful for the support I've received from my family and friends. And I've appreciated the support of everyone on the teams and in the broader community in the past, and count on that support now as I fight this challenge."
Allen was born in Seattle, Washington, where he was raised and eventually attended Lakeside School, the private learning institution where he first became friends with Gates.
In their teenage years the two worked in the computer labs at the nearby University of Washington, and upon graduating Allen spent two years at Washington State University.
He dropped out before getting a degree though and headed off to Boston, where he took a job as a computer programmer at Honeywell.
That put him close to Gates, who was two years younger and attending Harvard at the time. Once Gates dropped out of Harvard the two got started on their new company, putting a BASIC programming language interpreter on the market in 1975 and the following year starting to build a staff.
In 1978 Microsoft's revenue exceeded a million dollars and the next year the company moved from Albuquerque to Seattle.
Microsoft made its next leap forward in 1980 when the company was chosen by IBM to create the operating system for its first PC.
Microsoft bought the software for US$50,000 from another company and called it MS-DOS. Gates insisted that IBM let Microsoft keep the copyright on the operating system in a move that ultimately led to the company's fortune and persuaded his old Harvard friend Steve Ballmer to join Microsoft in 1980 as the business manager.
On August 12th, 1981, IBM introduced the first Personal Computer (PC), running on MS-DOS.
Two years later Microsoft introduced its 'Word' word-processing program and announced plans to create a Windows operating system. The first version of Windows was duly shipped out in 1985. By this point the company was worth $140million.
In 1986 Microsoft's stock went public. On the first day of trading, the share price rose from $21 to $28.
The next year a young Texan woman called Melinda French joined Microsoft as a marketing manager. She and Bill started dating.
By 1989 Microsoft introduced the earliest version of the Office business software suite. The next year Windows 3.0 was launched and sold 100,000 copies in two weeks. By 1991 Gates sent out a memo announcing the OS/2 partnership with IBM was over and they would focus on developing Windows.
The Federal Trade Commission started to investigate claims Microsoft was monopolising the PC market in 1991. However, the investigation closed two years later without a formal complaint.
Microsoft launched Windows 95 and online service MSN together in 1995. This was followed by Internet Explorer 2.0, challenging Netscape's Navigator Web browser.
Gates was the driving force behind the new online focus: 'I now assign the internet the highest level of importance,' he told senior staff in a memo.
In 1996 Microsoft released Internet Explorer 3.0 and Microsoft and Apple Computer agreed to share technology, setting aside a long-standing feud.
Netscape asked the Department of Justice to investigate Microsoft's discount to computer manufacturers that installed Internet Explorer 3.0. in 1996.
In 1997 the Justice Department sued Microsoft, saying it violated the 1994 consent decree by requiring computer makers to use its Internet browser as a condition of using Windows.
The next year the Justice Department and 20 states sued Microsoft, alleging it illegally thwarted competition. One state later dropped out of the suit.
The antitrust trial ran from October 1998 to the summer of 1999. In November US District Judge Thomas Penfield Jackson released his findings labelling Microsoft an 'abusive monopoly'.
In 2000, Gates stepped aside as CEO of Microsoft and gave the post to Steve Ballmer although he remained Microsoft chairman. He also took on the title of chief software architect.
That was also the year that Allen left Microsoft, agreeing initially to cede some shares in the company to Gates given that he would be handling a far greater workload.
In a last second move though, Gates offered to buy Allen at a very low price, resulting in Allen leaving the company with all his shares intact.
That move made him one of the richest men in the world.
In June of 2000, Judge Jackson ordered the breakup of Microsoft into two companies. The Supreme Court refused to hear Microsoft's appeal of Jackson's decision, sending the case to a federal appeals court.
The Court of Appeal overturned Judge Jackson's ruling to break up the company. However, it upheld his ruling that Microsoft illegally used licensing agreements with internet service providers and PC manufacturers to freeze out the Netscape browser.
Once he stepped away from Microsoft, Allen devoted himself to a number of charitable and philanthropic endeavors, including the Allen Institute for Brain Science.
The non-profit medical research organization was founded in 2003 by Allen and his sister Jody, and dedicated understanding the inner workings of the human brain.
Allen, the owner of 42 US patents, liked to cast himself as a technology visionary who drove Microsoft's early success and saw the future of connected computing long before the Internet.
"I expect the personal computer to become the kind of thing that people carry with them, a companion that takes notes, does accounting, gives reminders, handles a thousand personal tasks," Allen wrote in a column in Personal Computing magazine as far back as 1977, long before portable computers became a reality.
In the same year, he outlined an early vision of what turned out to be the Internet to Microcomputer Interface magazine.
"What I do see is a home terminal that's connected to a centralized network by phone lines, fiber optics or some other communication system," said Allen. "With that system you can perhaps put your car up for sale or look for a house in a different city or check out the price of asparagus at the nearest grocery market or check the price of a stock."
Allen later called this sweeping idea the 'wired world,' which has broadly come to fruition. He was not alone in predicting connected computing but was one of the most prominent.
Yet Allen's technology ventures after Microsoft, which focused on areas he thought would grow with the advent of the 'wired world,' were not as successful.
He lost $8 billion in the cable television industry, chiefly with a bad bet on cable company Charter Communications, while technology ventures he bankrolled such as Metricom, SkyPix and Interval Research were costly failures.
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