BrewDog, the fast-expanding craft beer firm, has apologised to former employees who accused the company and its co-founder James Watt of fostering a “culture of fear” in which workers were bullied and “treated like objects”. In an open letter circulated on Twitter, 61 former workers alleged that the Scottish brewer’s dizzyingly rapid growth had involved cutting corners on health and safety, espousing values it did not live by, and creating a “toxic” culture that left staff suffering from mental illness. “Growth, at all costs, has always been perceived as the number one focus for the company,” the letter alleges. “Being treated like a human being was sadly not always a given for those working at BrewDog.” They sent the letter under the banner “Punks with Purpose”, a nod to BrewDog’s flagship brand Punk IPA and the company’s self-styled image as a brash upstart taking on faceless corporate brewers. The Scottish brewer has been a key player in the rapid rise in the popularity of craft beer in the UK, spurred by tax relief on small breweries introduced by Gordon Brown as chancellor. It has grown rapidly since it was founded in 2007, helped by the backing of 130,000 “equity punks”, small shareholders who have helped crowdfund its growth. It now has 100 bars around the world, annual sales of £215m, and its beers are stocked in large supermarkets. Its evolution into a commercial force has been marked by a steady stream of controversies – but none with the sting of Thursday’s staff backlash. According to an internal staff memo seen by the Guardian, BrewDog initially considered hitting back, by rallying current employees to sign a response letter. The memo labelled the claims made by ex-staff about its working conditions “demeaning” and warned current employees that the allegations posed a “threat to all of our livelihoods”. But BrewDog decided against launching a counterpunch, instead issuing a contrite statement acknowledging some of its failings. “As a fast-growing business, we have always tried to do the best by our team — we do have thousands of employees with positive stories to tell as a result,” Watt said. “But the tweet we saw last night proves that on many occasions we haven’t got it right. We are committed to doing better, not just as a reaction to this, but always; and we are going to reach out to our entire team past and present to learn more. But most of all, right now, we are sorry.” Watt, who co-founded the company in 2007 with Martin Dickie, has issued public apologies before. In 2017, he admitted the company “got it wrong” after its lawyers pursued two small bars for trademark infringement, raising questions over its punk image. He has also been forced to back down after several publicity stunts misfired, including a mock “beer for girls” called Pink IPA that BrewDog said was meant to undermine stereotypes but which drew criticism from women in the beer industry. The latest apology came in response to claims that struck at the heart of BrewDog’s reputation and its repeated claims to be committed to equality, climate action and other progressive values. The strongly worded letter, signed by the 61 former staff, claims that a further 45 ex-employees supported the message but refused to share their names for fear of repercussions. “Put bluntly, the single biggest shared experience of former staff is a residual feeling of fear,” the letter says. “Fear to speak out about the atmosphere we were immersed in, and fear of repercussions even after we have left.” Directly addressing Watt in the letter, the signatories write: “It is with you that the responsibility for this rotten culture lies. Your attitude and actions are at the heart of the way BrewDog is perceived, from both inside and out. “By valuing growth, speed and action above all else, your company has achieved incredible things, but at the expense of those who delivered your dreams. In the wake of your success, people are left burnt out, afraid and miserable.” It also claims the company failed to follow through on promises made as part of PR campaigns, including sending beer to the Kremlin to mock Russia’s laws on “gay propaganda”. BrewDog also betrayed its eco-friendly policies, the letter claims, by chartering a private plane and brewing beer with glacier water, “half of which was dumped down the drain”. BrewDog did not respond to these claims.