David Duggan* was so impressed with the ability of the Claude chatbot to answer medical questions and organise family life, that a $20-a-month (£15) subscription seemed like money well spent.

But then his wife spotted two $200 payments on his credit card bill for gift cards to use the artificial intelligence tool.

Duggan, who lives on the east coast of the US, had not bought them, and immediately realised something was wrong.

“My wife asked me: ‘Hey, did you make these $200 purchases?’ It was $400 in total. And then there was a third one, but that needed a confirmation and did not go through,” he says.

When he contacted Anthropic, the company behind the Claude family of AI tools, his account was suspended, but the computer-generated responses to his questions did not shed any light on what had happened.

He started searching online for other victims, and found that a number of Claude users had had similar experiences and detailed them on online forum Reddit.

One person reported that 10 payments, each for £18, had been taken from his account. Another said they had been charged €216 (£186) three times. Two people had been charged €225 each out of the blue.

Adding to Duggan’s concern was that the genuine vouchers were sent to his personal email. This led him to worry that his email had also been hacked and that fraudsters were able to access the vouchers, exposing him to more scams.

After the fraud, Duggan changed his credit card details online and this action prevented two more payments being processed. He is now working with his bank to get his money back.

What it looks like

Payments show up on a bank statement as going to Anthropic. One Reddit user showed an email to say “You’ve received a gift!” and that a subscription to Claude has been sent to them. A link is provided to redeem the gift.

What can be done

Anthropic says it is putting new protections in place to prevent fraudulent gift card purchases. When it identifies scam purchases, it says the subscriptions are cancelled and refunds issued.

If you do come across a payment that you don’t recognise, contact the company’s support. It promises to refund any charges that have not already been reversed. The company advises cancelling the affected bank card and requesting a new one, while also changing login details on the site.

However, it says there was no evidence that compromised card details had originated from Anthropic.

If you notice a payment that you didn’t authorise, contact your bank or credit card firm to make a chargeback claim. It’s important that you report suspected fraud immediately so your bank can block your card and secure your account. They may ask some questions and get you to fill out a form stating what happened.

* Name has been changed