According to police spokesman Sgt. Wilfred Williams, the man, described as an Asian male, "appeared to have committed suicide" at about 11:46 p.m. in the 2200 block of Beach Street.
The man, whose name has not yet been released by the San Francisco medical examiner's office, was pronounced dead at San Francisco General Hospital, Williams said.
According to Williams, the man had recently been evicted from his business, located in another part of the city, and was also recently divorced.
Apart from the "Free Tibet" sign, Williams said there was "no further evidence" linking the apparent suicide "with any political cause."
"We're investigating the case, and the manner and cause of death are pending," said San Francisco medical examiner's office Administrator Steve Gelman.
View video taken by Students for a Free Tibet of the Golden Gate Bridge protest here.
For Olympic Torch schedule and information, including street closures and the six-mile route through San Francisco, click here.
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