StubHub has been accused of failing to disclose when customers are buying tickets from professional touts, in breach of a legal undertaking given to the consumer watchdog. The Competition and Markets Authority (CMA) requires sites such as Viagogo and StubHub to let customers know when tickets are being sold by professional ticket traders, who dominate resale listings for gigs and other events, leading to fans paying massively inflated prices. In responses to the Guardian, StubHub insisted that it abided by this requirement, intended to ensure customers know who to contact if they have a problem. This can include being refused admission at the door because resale sites have continued to sell tickets for gigs even where resale is not permitted. Fresh analysis of the StubHub website earlier this week found that listings for tickets to see artists such as Adele and Coldplay did not include any details of sellers, prompting concern from an MP and campaigners. While some listings may be from ordinary fans who can’t attend and want to recoup their money, a report by the CMA this year found that touts are typically behind more than 50% of tickets listed on Viagogo and StubHub. Sources in the touting world said that some had tried to upload the required information, but found that it did not appear on the StubHub website. The Guardian also cross-referenced events on Viagogo and StubHub, and found that the exact seats at the same shows were disclosed as being advertised by touts on the former site but not on the latter. Shortly after the Guardian asked StubHub about the disclosures, some trader details began appearing on the site. Viagogo bought StubHub last year but was forced by the CMA to sell the UK and EU operations after a competition inquiry. Digital Fuel Capital (DFC) stepped in to buy StubHub UK. Labour MP Sharon Hodgson, who is the chief parliamentary aide to party leader Keir Starmer, said the apparent lack of disclosure by StubHub “should be ringing alarm bells at the CMA”. She said StubHub appeared to be “rowing back on their legal obligations”, including an undertaking given to the CMA as part of its investigation into breaches of consumer law by both Viagogo and StubHub, many of them revealed in the Guardian. “Either the evidence presented to the CMA stands up or it doesn’t,” she said. “If it does, then I would urge them to do their job, to start enforcement action, and help protect British consumers.” Adam Webb, of music industry group FanFair Alliance, backed by the managers of bands including Arctic Monkeys, said evidence that consumer protection laws were being broken was “clear cut”. “I can only assume the CMA is either ignoring this evidence, or they don’t believe it’s important enough to intervene,” he said. The CMA said would take “appropriate action” if there was evidence firms were failing to comply with consumer law. StubHub said it was “fully compliant” with the requirement to publish touts’ details. “As the CMA undertaking stipulates, if we are made aware of non-compliance, we take corrective action to remove listings and notify sellers,” said a spokesperson.