Phia, a shopping startup co-founded by Phoebe Gates and Sophia Kianni, has been accused of cookie stuffing that diverted affiliate commissions from legitimate referrals, according to a Bloomberg investigation. The practice involves inserting its own tracking cookie during a user’s checkout, overriding any existing affiliate codes and claiming credit for purchases the user initiated independently. Phia’s browser extension, launched in 2025, helps shoppers compare prices and apply discount codes, earning commissions on sales it drives. An independent consultant and a competitor found that the extension opened background tabs and replaced referral codes even when users arrived directly at retailer sites. The allegation led to Phia’s suspension from Impact.com, an affiliate platform, and prompted scrutiny from retailers and affiliate partners. Phia said it had implemented fixes after the issue was raised, and a subsequent Bloomberg check indicated the problem was resolved, though questions remain about retailer acceptance. The company has not responded to requests for comment, and the outcome of the investigation remains uncertain.