Remember those friends you deleted long ago? Facebook does
When I downloaded a copy of my Facebook data last week, I didn’t expect to see much. My profile is sparse, I rarely post anything on the site, and I seldom click on ads. (I’m what some call a Facebook “lurker.”)
But when I opened my file, it was like opening Pandora’s box.
With a few clicks, I learned that about 500 advertisers — many that I had never heard of, like Bad Dad, a motorcycle parts store, and Space Jesus, an electronica band — had my contact information, which could include my email address, phone number and full name. Facebook also had my entire phone book, including the number to ring my apartment buzzer. The social network had even kept a permanent record of the roughly 100 people I had deleted from my friends list over the last 14 years, including my exes.
There was so much that Facebook knew about me — more than I wanted to know. But after looking at the totality of what the Silicon Valley company had obtained about yours truly, I decided to try to better understand how and why my data was collected and stored. I also sought to find out how much of my data could be removed.
How Facebook collects and treats personal information was central this week when Mark Zuckerberg, the company’s chief executive, answered questions in Congress about data privacy and his responsibilities to users. During his testimony, Zuckerberg repeatedly said Facebook has a tool for downloading your data that “allows people to see and take out all the information they’ve put into Facebook.”
But that’s an overstatement. Most basic information, like my birthday, could not be deleted. More important, the pieces of data I found objectionable, like the record of people I had unfriended, could not be removed from Facebook, either.
“They don’t delete anything, and that’s a general policy,” said Gabriel Weinberg, the founder of DuckDuckGo, which offers internet privacy tools. He added that data was kept around to eventually help brands serve targeted ads.
Beth Gautier, a Facebook spokeswoman, put it this way: “When you delete something, we remove it so it’s not visible or accessible on Facebook.” She added: “You can also delete your account whenever you want. It may take up to 90 days to delete all backups of data on our servers.”
Digging through your Facebook files is an exercise I highly recommend if you care about how your personal information is stored and used. Here’s what I learned.
When you download a copy of your Facebook data, you will see a folder containing multiple subfolders and files. The most important one is the “index” file, which is essentially a raw data set of your Facebook account, where you can click through your profile, friends list, timeline and messages, among other features.
One surprising part of my index file was a section called Contact Info. This contained the 764 names and phone numbers of everyone in my iPhone’s address book. Upon closer inspection, it turned out that Facebook had stored my entire phone book because I had uploaded it when setting up Facebook’s messaging app, Messenger.
This was unsettling. I had hoped Messenger would use my contacts list to find others who were also using the app so that I could connect with them easily — and hold on to the relevant contact information only for the people who were on Messenger. Yet Facebook kept the entire list, including the phone numbers for my car mechanic, my apartment door buzzer and a pizzeria.
Facebook also kept a history of each time I opened Facebook over the last two years, including which device and web browser I used. On some days, it even logged my locations, like when I was at a hospital two years ago or when I visited Tokyo last year.
Facebook keeps a log of this data as a security measure to flag suspicious logins from unknown devices or locations, similar to how banks send a fraud alert when your credit card number is used in a suspicious location. This practice seemed reasonable, so I didn’t try to purge this information.
But what bothered me was the data that I had explicitly deleted but that lingered in plain sight. On my friends list, Facebook had a record of “Removed Friends,” a dossier of the 112 people I had removed along with the date I clicked the “Unfriend” button. Why should Facebook remember the people I’ve cut off from my life?
Facebook’s explanation was dissatisfying. The company said it might use my list of deleted friends so that those people did not appear in my feed with the feature “On This Day,” which resurfaces memories from years past to help people reminisce. I’d rather have the option to delete the list of deleted friends for good.
What Facebook retained about me isn’t remotely as creepy as the sheer number of advertisers that have my information in their databases. I found this out when I clicked on the Ads section in my Facebook file, which loaded a history of the dozen ads I had clicked on while browsing the social network.
Lower down, there was a section titled “Advertisers with your contact info,” followed by a list of roughly 500 brands, the overwhelming majority of which I had never interacted with. Some brands sounded obscure and sketchy — one was called “Microphone Check,” which turned out to be a radio show. Other brands were more familiar, like Victoria’s Secret Pink, Good Eggs or AARP.
Facebook said unfamiliar advertisers might appear on the list because they might have obtained my contact information from elsewhere, compiled it into a list of people they wanted to target and uploaded that list into Facebook. Brands can upload their customer lists into a tool called Custom Audiences, which helps them find those same people’s Facebook profiles to serve them ads.
The upshot? Even a Facebook lurker, like myself, who has barely clicked on any digital ads can have personal information exposed to an enormous number of advertisers. This was not entirely surprising, but seeing the list of unfamiliar brands with my contact information in my Facebook file was a dose of reality.