Cutting corners: CNBC has discovered that every Gmail account has a purchases record attached to it, built on data gathered from digital receipts sent to the account, purchases made on Google services like the Play Store, and purchases made on accounts linked to a Gmail address. Go and check your own purchase record - how much data has Google been secretly collecting on you?

It's been two years since Google formally declared they would stop using the data they gathered from Gmail for ad targeting purposes, yet here we stand: they're collating massive amounts of purchasing information supposedly "to help you easily view and keep track of your purchases," without telling you they're doing so. The only way to delete that purchase record is by deleting every single email receipt you've ever received, one by one. Oh, and though Google says you can turn off purchase tracking in settings, no one can actually find the setting.

For some people, this isn't an issue. Personally, I don't use my Gmail very often and I don't make purchases online, so my purchase record only contains my Steam games and a few Play Store purchases. But for many of the one-and-a-half billion users of Gmail, their purchase records will contain their weekly shopping itinerary, Amazon purchase history, and details on what they wear and what they watch. For a significant portion of Gmail users, the purchase record 'feature' may be Google's most invasive product and one they've never heard of.

Just last week, Google CEO Sundar Pichai wrote in the New York Times: "To make privacy real, we give you clear, meaningful choices around your data. All while staying true to two unequivocal policies: that Google will never sell any personal information to third parties; and that you get to decide how your information is used."

The second 'policy' looks like a bare-faced lie in light of today's discovery, and the first 'policy' is meaningless when Google is just as likely to mistreat your data as any third-party.

How much you trust Google is up to you, but it's worth noting that a history of your purchases is by far the most useful data point for predicting future purchases. While it's probably true that Google doesn't "use any information from your Gmail messages to serve you ads," they might be using all that data to feed AIs, develop consumer spending models, and to determine how successful their targeted advertising is.

Unfortunately, deleting your purchase record is an irritating process that requires you to forward all receipts to a non-Gmail email account if you want to keep them. To see the offending emails, click on a purchase in the record then hit "Remove Purchase" at the bottom.

For the privacy conscious, the best way to prevent Google from continuing to record your purchases is to switch to a new email provider. Personally, I recommend finding a service like Tutanota, an open-source end-to-end encrypted email service. To distance yourself even further from Google, try a non-Chrome browser like Vivaldi or Firefox and switch to DuckDuckGo for searches.