Costco shoppers, beware: your personal information may have been compromised and shared with tech behemoth Meta, according to a new lawsuit.
In documents filed in Seattle Federal Court, the class-action lawsuit alleges that Costco was using Meta Pixel on the healthcare area of its website without customers’ knowledge or consent.
Meta Pixel is an analytical tool that allows a website to track visitor activity, and Meta would be able to see visitors’ personal and healthcare information submitted through the site.
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“By secretly recording and transmitting data to Meta — without the user’s knowledge or consent — Pixel acts much like a traditional wiretap,” the lawsuit states, per The Seattle Times. “Costco fails to disclose or omits the fact that it shares patient online activities and personal health information with Meta via Pixel.”
The lawsuit says Costco tells patients and customers that its website uses a “secure platform,” but by using the tracking service, it is violating its own policy.
Data potentially shared includes prescription information, patient location, health insurance coverage, immunization information, and more.
Costco Pharmacy offers services such as prescription delivery and scheduling vaccines.
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The lawsuit alleges that Pixel’s data would help Costco and Meta “build profiles” around each patient and their behaviors and medical needs, which would eventually be used to maximize targeted marketing.
Costco told The Seattle Times that it would not comment on pending litigation, though Meta condemned the notion it uses the data recorded through Pixel for marketing purposes.
“Advertisers should not send sensitive information about people through our business tools,” Meta said Monday, as Costco is considered one of its advertisers. “Doing so is against our policies, and we educate advertisers on properly setting up business tools to prevent this from occurring.”
Neither Costco nor Meta immediately responded to Entrepreneur’s request for comment.
This story originally appeared on Entrepreneur