The key is the last line in the paragraph under "Choice." It has a hyperlink, "click here," that unfurls a form that will allow a person to "opt out of all Datalogix-enabled advertising and analytic products."
Ironically, opting out of Datalogix's program with Facebook involves disclosing personal data to Datalogix, including a person's name, email address and physical address. The form must be completed by every member of a household, Datalogix advises. An opt-out request will be honored within 30 days.
Facebook confirmed on Thursday that the submission will stop the data sharing: "When you opt out of Datalogix analytics research, the data provided by retailers to Datalogix is not included in the aggregate measurement reports that are generated for our advertisers."
The digital rights group Electronic Frontier Foundation advised on its blog that if people are uncomfortable with this kind of data sharing, they best not sign up to loyalty card programs in the first place.
"Many people who sign up for loyalty programs may not realize the data amassed on them will be shared with entities outside of the store," the organization wrote.
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