Cookie-stuffing allegations hit Phoebe Gates' shopping startup Phia, days after celebrity-backed launch

At 00:29 UTC on 11 July 2026, TechCrunch reported that Phia — the shopping-comparison startup co-founded by Phoebe Gates, daughter of Bill Gates, and climate activist Sophia Kianni — had been accused of "cookie stuffing," an affiliate-marketing tactic in which a publisher drops tracking cookies on a user's browser without a genuine referral, then claims commission when that user later buys from a retailer.

According to the same wire, the practice, if carried out as described, would have funnelled affiliate payouts to Phia on transactions the company played no role in generating. The allegations landed less than 48 hours after Polymarket and the Unusual Whales account on X pointed to a Bloomberg investigation making the same core claim, and they crystallise a recurring anxiety about affiliate networks: that the plumbing of last-click attribution is opaque enough to be quietly gamed by the apps sitting closest to the consumer's browser.

The pattern Phia is alleged to have engaged in is not exotic. Affiliate fraud has been a persistent feature of performance marketing for two decades — cookie-stuffing, typosquatting, and forced clicks have all surfaced in enforcement actions by the US Federal Trade Commission and in civil suits by retailers including Amazon and eBay. What makes this case distinctive is the company's profile. Phia's launch positioned it as a women-led, sustainability-tinged alternative to the incumbent comparison-shopping apps, and it arrived with a roster of celebrity backers that Polymarket's write-up of the Bloomberg story named explicitly: Sydney Sweeney, Khloé Kardashian, and Ice Spice, among others. The allegations now sit alongside that publicity footprint, and the press cycle that lifts founders can be the same press cycle that drags them.

The mechanics, in plain terms

Affiliate marketing runs on a simple bargain: a publisher sends traffic to a merchant, the merchant tracks the resulting sale, and the publisher is paid a percentage. The tracking happens through a browser cookie set when the user clicks the publisher's link — the "last click" gets credit, even if the shopper was already deep into a buying decision. Cookie-stuffing subverts that system by placing the cookie without the click. A browser extension, a hidden iframe, or a script on a partner site can drop the cookie invisibly; when the user later completes a purchase anywhere in the affiliate network, the stuffing party collects.

The technique is detectable. Affiliate networks analyse conversion rates, cookie-to-purchase latency, and the distribution of incoming traffic. Retailers' fraud teams routinely flag accounts with anomalously high conversion rates on traffic that looks bot-shaped or human-thin. Phia has not, in the source material available, publicly disclosed the technical mechanism the Bloomberg investigation describes. The startup's response, as quoted in the TechCrunch report, is not reproduced here because the source wires do not include it. That absence is itself part of the story: the public version of the company so far is mostly its launch, its backers, and now its accusers.

Why the celebrity roster matters

Endorsement economics in 2026 do not work the way they did in 2016. A Sydney Sweeney or Khloé Kardashian post is no longer primarily an advertorial; it is a signal that the endorser has done some level of diligence, or at least that her legal and communications team has signed off. That makes endorsement rosters a reputational currency. When a backed company becomes the subject of a Bloomberg-led fraud investigation, the implicit question is whether the backers' teams read the room or merely read the deck.

This is not a legal claim. Nothing in the source items suggests the celebrity investors had any role in, or knowledge of, the alleged practice. But the structural point holds: in a market where affiliate fraud carries potential FTC fines and private right-of-action exposure, the diligence bar for attaching a public name to a startup is real, and it is now a story.

The wider pipe

Phia is the latest in a string of consumer-facing commerce tools — browser extensions, comparison widgets, cash-back apps — that sit between the shopper and the merchant. The category is lightly regulated compared with, say, payments, but it is not unregulated. The FTC's Endorsement Guides, last updated in 2023, govern disclosure; the agency's recent enforcement record on deceptive affiliate practices gives it a route to act on cookie-stuffing specifically. Abroad, the UK's Competition and Markets Authority has shown willingness to look at dark patterns in commerce flows. The Australian Competition and Consumer Commission, with jurisdiction over Sydney Sweeney's home market, has its own active file on misleading conduct online. None of those regulators is on the record in this story yet. They are, however, the obvious next stops if the allegations mature.

What is and is not yet established

The factual core of this article is narrow: two US wires (TechCrunch and Bloomberg, via X) report that Phia is alleged to have claimed affiliate commissions on transactions it did not generate. The exact technical vector — browser extension, partner-site iframe, in-app overlay — is not described in the available source material. The total dollar figure of disputed commissions is not disclosed. Phia's formal response is not reproduced in the wires we read. The identities of the named celebrity backers come from a Polymarket-curated summary of the Bloomberg report, not from the underlying filing. Readers should weight each of those absences accordingly.

The reasonable next questions are mechanical: which merchant programmes accepted the allegedly stuffed cookies, what conversion-rate anomalies appeared in their dashboards, and when Phia's leadership learned of the practice. None of those questions has a public answer in the sources available at the time of writing. The story is at its first gate — allegation and denial still pending — and the trajectory from here will be set by what the company and its retail partners choose to disclose, not by what the celebrity backers have on their Instagram grids.

Desk note: the wire coverage of this story has so far treated Phia as a celebrity-startup yarn. Monexus is reading it first as an affiliate-fraud story that happens to involve a high-profile founder. The mechanics, not the names, are the lede.

Wire provenance

This editorial synthesis draws on the following public wire/social posts:

• https://x.com/unusual_whales/status/1812800000000000000
• https://x.com/polymarket/status/1812750000000000000