A class-action complaint filed Tuesday in the Western District of Washington by Boycat Inc. alleges that Microsoft’s shopping browser extension unfairly takes commissions from online marketers, such as influencers and website operators.
The complaint says that the Microsoft Shopping browser extension comes pre-installed on every Windows PC as part of the Microsoft Edge browser.
The extension is described by Microsoft as a free tool that helps online shoppers find coupons, compare prices, and earn cashback.
According to the lawsuit, Microsoft claimed shoppers have saved more than $12.4 billion through the extension.
The plaintiff alleges that the browser extension is designed to steal commissions by manipulating online traffic and network transmissions.
According to court documents, the extension does this by altering the tracking tags and marketing cookies, which online retailers use to identify what website or person should get credit for a referral and subsequent sale.
The filing describes a practice in affiliate marketing in which online marketers earn money by creating unique affiliate links that direct potential customers to a retailer’s website.
If a customer clicks on the link, cookies and tracking tags are created, allowing the retailer to know that the sale was the result of the affiliate link.
Under the typical practice, the online marketer who created the link would receive a commission.
The lawsuit alleges that when a shopper uses the Microsoft Shopping browser extension, it invisibly removes these affiliate cookies and tracking tags.
They are replaced by Microsoft’s own cookies, effectively giving Microsoft credit for the sale and the related commission.
The class action includes all people in the United States who participated in an affiliate commission program with a U.S. e-commerce merchant whose commissions were diverted to Microsoft because of the extension.
The filing says the lawsuit seeks damages and a court order to stop Microsoft’s actions.
Boycat Inc. is an online content creator that earns commissions through affiliate marketing links.
The filing states that Boycat earned about $1,000 over the last year in commissions, but it would have earned more if not for Microsoft’s actions.
The company argues it is still facing harm because Microsoft continues its alleged practice of stealing commissions.
The lawsuit includes claims for unjust enrichment, violation of California’s Business and Professions Code, violation of California’s Unfair Competition Law, tortious interference with prospective economic advantage, conversion, and violation of Washington’s Consumer Protection Act.
KIRO 7 News has reached out to Microsoft for comment.
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