SAN FRANCISCO (AP) — California's ballot measure to legalise marijuana has a new friend: Facebook co-founder Sean Parker has given $100,000 to back the proposal.

Parker's donation was reported in Proposition 19 campaign finance filings this week.

And he's not the first big Proposition 19 donor with ties to the social networking site. Facebook co-founder Dustin Moskovitz has made two donations totalling $70,000, including a $50,000 contribution last month.

Neither Parker nor Moskovitz is still with Palo Alto-based Facebook, but both still have ownership stakes. Recent estimates put the value of the privately held company as high as $33.7 billion.

"What's interesting here is that (Parker) is a member of the generation that really gets it," said Stephen Gutwillig, a spokesman for the Drug Policy Alliance, the main beneficiary of Parker's contribution. "We think he's pivotal to the future of drug policy reform in the country."

The 30-year-old served as Facebook's first president and helped transform the company from dorm-room project to big business. Parker and Moskovitz have become household names since the recent release of "The Social Network." The film chronicling the contentious origins of Facebook was No. 1 at the box office last week.

At age 19, Parker helped develop Napster, the music-sharing software that turned the recording industry upside-down. He is now a partner at Founders Fund, a Silicon Valley venture capital firm.

Parker did not immediately respond to e-mails seeking comment.

About $1.5 million of the $2.4 million raised so far in support of Proposition 19 has come from the measure's main sponsor, Oakland medical marijuana entrepreneur Richard Lee. The only other six-figure donation not from Lee came from adult entertainment entrepreneur Phil Harvey, who gave $100,000.

Parker's donation came shortly after the Yes on 19 campaign committee reported having meager cash on hand heading into the final weeks before the election. The money from Parker and Harvey went to a separate committee to fund the Drug Policy Alliance's work on behalf of the measure.

Much of the money will go toward a get-out-the-vote campaign targeting young voters and voters of color, Gutwillig said.

Facebook recently came under fire from some marijuana advocates who claimed it was turning away advertising on the site in support of Proposition 19. Facebook said in a statement that company policy prohibits images of drugs, drug paraphernalia or tobacco in paid advertising but that ballot measure supporters were still free to advertise using different images.