Bill Gates' Daughter Phoebe's App Accused of 'Cookie Stuffing'

Bill Gates' daughter is getting some heat after her app allegedly took credit for sales it didn't drive ... and a new report claims she knew it was happening.

People with knowledge of the matter told Bloomberg that Phoebe Gates and her Phia co-founder Sophia Kianni had allegedly known about the practice since December and shared internal Slack messages about it.

A Phia spokesperson had told the outlet back in July that they'd become aware of the "misattributions" only within the last 24 hours, saying at the time ... "As soon as we were notified, our team worked overnight to identify, mitigate, and has since resolved the issue."

But, according to Bloomberg, this new information tells a completely different story ... that Phoebe and Sophia were allegedly knowingly participating in "cookie stuffing."

Here's the deal ... Phia -- a price comparison, e-commerce app -- implements a browser extension that helps shoppers find discount codes as part of the checkout process.

As a result, the company earns commission from the partnering retailer when a purchase is made using the app.

The problem was the extension was also fraudulently reporting that Phia was driving sales even when their product wasn't used.

Bloomberg says the app would set a web tracking device known as a cookie into the checkout process.

In a new statement, a Phia spokesperson told multiple outlets ... "Any features causing misattributions were immediately removed over a month ago on July 7."

They say they're working on issuing transaction reversals to brand partners and are hiring a head of compliance to prevent something similar from happening in the future ... but didn't acknowledge that Phoebe and Sophia were allegedly aware of the cookie stuffing.