Founders Fund, the venture capital firm co-founded by billionaire Peter Thiel, closed almost all of its eight-year bet on cryptocurrencies shortly before the market began to crash last year, generating about $1.8bn in returns.

The San Francisco-based fund made its first investment in bitcoin in early 2014 and went on to invest large sums in crypto. About two-thirds of its overall investment was used to buy bitcoin, said people close to the fund.

Founders Fund sold out of the vast majority of its entire cryptocurrency portfolio by the end of March 2022 — before the digital assets market became swept up in a crisis in May last year, said one of the people close to the fund.

The fund currently has no significant exposure to cryptocurrencies, the people said. The winding down of its crypto bet has not previously been reported. Founders Fund declined to comment.

Thiel, a big backer of Republican candidates and a supporter of former US president Donald Trump, was one of the earliest mainstream investors to buy large sums of bitcoin and has subsequently been loudly bullish on the digital currency.

In April 2022, about the same time that Founders Fund sold out of most of its cryptocurrency holdings, Thiel said he was optimistic about the future of bitcoin. He told a cryptocurrency conference in Miami that “we’re at the end of the fiat money regime” and suggested its price — which was then trading at about $44,000 — could increase by a factor of 100.

Thiel said JPMorgan chief executive Jamie Dimon and BlackRock boss Larry Fink “need to be allocating some of their money to bitcoin”, adding: “We need to push back on them.”

The price of bitcoin, which was first launched in 2009, surged dramatically from roughly $750 in 2014 to an all-time high of more than $65,000 by November 2021. However, its price has been volatile in recent years, with several major collapses in value, including a drop to about $15,500 in November last year, a two-year low.

The digital assets market has been rocked by a crisis since May last year, forcing high-profile crypto companies such as Terraform Labs, Celsius, Voyager and Three Arrows Capital into bankruptcy.

Market sentiment towards crypto was damaged further in November when FTX, the second-largest cryptocurrency exchange, shut down owing creditors more than $3bn, and its co-founder Sam Bankman-Fried was charged with multiple fraud charges.

By December, bitcoin had lost about three-quarters of its value from its peak and more than $2tn had been wiped off the value of the global crypto market.

Several blue-chip Silicon Valley investors have piled into digital currencies in recent years, although most have focused their investments on equity stakes in crypto businesses rather than buying cryptocurrencies directly.

Some exceptions to this include A16z crypto — the crypto arm of venture firm Andreessen Horowitz — which raised a $4.5bn fund last year and also invests directly in crypto coins and tokens.

Similarly, Paradigm, a crypto venture firm founded in 2018 by Coinbase co-founder Fred Ehrsam and former Sequoia Capital partner Matt Huang, raised a $2.5bn fund in late 2021.

But many large financial institutions stayed away from cryptocurrencies over fears about cyber security and their links to money laundering and drug trafficking. In 2017, JPMorgan’s Dimon called bitcoin a “fraud”.

Founders Fund’s shift on crypto, which had been one of its core positions, was one of about nine big exits the venture fund made between 2020 and the end of last year that allowed it to return roughly $13bn to investors.

Other exits also included the initial public offerings of companies it had backed since their early fundraisings, such as Airbnb and Palantir, the data analytics group that was Thiel co-founded.

Thiel co-founded PayPal in 1998 and went on to become one of Silicon Valley’s most successful investors, including being the first venture capitalist to back Facebook.

Founders Fund has more than $11bn under management, including $5bn of capital raised across two funds last year, and has taken stakes in more than 100 companies, such as Elon Musk’s SpaceX, ride-hailing app Lyft and defence tech group Anduril.

More recently, the fund is in talks to take an equity stake in OpenAI, the developer behind chatbot ChatGPT, at a valuation of $29bn.