Thiel considering big investment in pot sector: Source

Venture capitalist Peter Thiel—who famously suggested on CNBC that "pot smoking" was happening at Twitter—is considering a multimillion dollar investment in Privateer Holdings, a Seattle-based private equity firm that's among the first to invest in the cannabis space, a source confirmed to CNBC.

The source, who declined to be identified, has knowledge of Thiel's Founder's Fund.

The potential investment was reported at $75 million by Business Insider. But the source said that amount is inaccurate, and that the figure being discussed is closer to half of that figure.

If the Founder's Fund were to invest in Privateer, an announcement would likely be made in a few days, the source said. Founder's Fund also is not leading a Series B round, the source said. but the source would not confirm who's leading the investment round.

Twitter 'horribly mismanaged': Thiel
Twitter 'horribly mismanaged': Thiel

Appearing on CNBC in September, Thiel had a lot to say about Twitter and marijuana.

"Twitter is hard to evaluate," Thiel said on CNBC's "Squawk Box." "They have a lot of potential. It's a horribly mismanaged company—probably a lot of pot-smoking going on there. But it's such a solid franchise it may even work with all that," said the co-founder of PayPal.

Privateer Holdings has more than 40 investors and has raised more than $50 million to date. Privateer's founder Brendan Kennedy told CNBC last month that he's waiting on more clarity from the federal government before the firm begins investing in companies that actually touch marijuana. He made the comments at last month's Marijuana Conference and Expo in Las Vegas.

"The disparity between state and federal laws has given us a lot of concern," Kennedy said.

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Privateer's only acquisition so far is Leafly, also based in Seattle. Leafly serves as the Yelp of the cannabis industry, helping users find the right strains of product and as an information hub for patients.

Privateer did not immediately respond to a CNBC request for comment. Thiel could not immediately be reached through Founder's Fund.