This afternoon both Meta and LinkedIn sent me emails saying that my exports were available to download. So I downloaded.
The Meta files were huge!
About eight years ago, I stopped doing much on Facebook. The things I might have uploaded then would have accounted for less storage than today’s large photos and high-res videos. All the same, the export from my Facebook account amounted to a sizeable 876 megabytes.
And the export from Instagram came in two parts: 2.69 gigabytes and 1.26 gigabytes.

In small grey type at the foot: “Your export won’t include information that someone else shared, such as another person’s photos that you’re tagged in.” So photos of me, uploaded by someone else, won’t feature in my download. Hm.
***
By comparison, the export from LinkedIn was very light: just 1.4 megabytes.
I opened the Facebook folder, and found lots of folders inside it. Inside one of them was a file called “advertisers_using_your_activity_or_information.json”. I opened it.
About 9,000 lines. Which turn out to be 2,953 companies holding information about me.
They come in two groups.
The bigger group, 2,221 of them, is headed “Interactions you may have had with the advertiser’s website, app or store”. Fair enough. I have been on the internet.
The other group is 766 companies, and its heading is different. “A list uploaded or used by the advertiser.” Somebody had my details in a file, and put the file into Facebook.
That group includes Abel & Cole, who deliver my vegetables. It includes The School of Life, where I taught for seven years. It includes Jackson’s Art, the Barbican and the London Review of Books, all of which I signed up to on purpose and would sign up to again.
It also includes Acxiom. And Epsilon Audience Data Provider. And Experian Marketing Services – Audiences. I had never heard of any of them.
Their business is holding lists of people and selling access to those lists.
The file records both kinds in exactly the same way. One column, one format, no distinction at all between the company I chose and the company I have never met.
So there we are. I spent time looking into just one file – in just one of the folders.
Much more still to investigate.
***