Brewdog co-founder James Watt says he has made an offer to buy back the craft beer business months after it was sold to a US company.

At its peak, Brewdog had four breweries, about 100 pubs worldwide and was said to be worth more than $1bn.

However, it was bought over by beverage and medical cannabis company Tilray earlier this year after collapsing with debts of more than £500m, leading to hundreds of job losses.

Watt – who co‑founded the firm with Martin Dickie in Aberdeenshire almost 20 years ago – said investors in Brewdog’s “Equity for Punks” scheme would receive shares “for free” if his takeover bid was successful.

About 20,000 people invested in the scheme, typically spending about £500 on shares costing £20-30 each. They were left worthless as the firm collapsed.

Watt stood down as chief executive in 2024 and moved to a newly created position of “captain and co-founder”. Dickie left the company last year, citing personal reasons.

Both had sold shares in the firm to a US private equity fund TSG in 2017, making £50m each.

After leaving Brewdog, Watt launched a new beer brand, Second Best, offering nearly 20% of shares to people who lost money after investing in Equity for Punks.

Former investors told the BBC that they were sceptical about those plans.

In an email to those who signed up to the Second Best offer, seen by BBC Scotland News, Watt said he had made an official offer to buy back Brewdog.

He wrote: “If successful, everyone who has signed up to Second Best will own the same stake in Brewdog they once held. For free.”

Watt added that the firm “should be owned by the equity punks and I will endeavour to ensure that happens”.

The Aberdeenshire businessman was previously involved in a bid to buy back the firm following its collapse, but lost out to Tilray.

Watt recently apologised to staff and investors for the “many mistakes” made in the management of the company, admitting that it tried to diversify too quickly.

Brewdog’s brash marketing style had regularly sparked controversy, but the firm also faced criticism for its treatment of investors and staff.

A 2022 a BBC Disclosure investigation uncovered claims of inappropriate behaviour by Watt towards female staff, and revealed that Brewdog violated import laws and fabricated many of its marketing stories.

In 2024, the firm faced a backlash after revealing it would no longer hire new staff on the real living wage, instead paying the lower legal minimum wage.

Watt denied any wrongdoing alleged in the film and threatened to sue the BBC. He later said he sometimes missed social cues because he has autism.

A complaint to broadcasting regulator Ofcom was rejected.

Brewdog said it was putting in a range of measures to improve workplace culture following the release of the programme.

Tilray and Second Best have been asked to comment on Watt’s letter.