FILE PHOTO: Sam Altman, President of Y Combinator, speaks at the Wall Street Journal Digital Conference in Laguna Beach, California, U.S., October 18, 2017. REUTERS/Lucy Nicholson

SAN FRANCISCO (Reuters) - Sam Altman is stepping down from his post as president of Y Combinator, the startup accelerator said on Friday, a pivotal change for the organization that was influential in the creation of startups such as Airbnb, Dropbox Inc and Cruise.

As YC’s second-ever president, Altman spent five years expanding the program’s reach and scale. He will move on to spending more time working on artificial intelligence efforts while remaining chairman at the company, YC said in a blog post Friday.

YC offers a startup program to which aspiring entrepreneurs can apply to receive mentorship and a $150,000 investment, and participate in a three-month bootcamp to work on their startup idea. YC gained influence in the tech industry after a number of startups that completed the program went on to achieve high valuations and be acquired by big companies. Cruise, for instance, was acquired by General Motors Co for $1 billion, and Airbnb, valued at $31 billion, is preparing for an IPO this year.

Of course, many YC graduates fail, too.

Many entrepreneurs apply to YC for the access to Silicon Valley venture capitalists; every YC program ends with a Demo Day when startups can show off their budding companies to prospective investors.

YC also said on Friday it plans to move to San Francisco from Mountain View, California, the latest sign of how startup activity has moved away from what was traditionally Silicon Valley and concentrated in San Francisco.

Under Altman’s leadership, YC expanded beyond nascent startups and created a separate fund and training program for larger, more mature tech companies. It also expanded into China and added a host of other startup programs.

Altman has become one of the startup industry’s more outspoken leaders on issues such as universal basic income and the safety and ethical implications of artificial intelligence. He helped found non-profit AI research organization OpenAI.

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