And if a friend had put your name and phone number in their phone, and they synced their contact list with FB and merged the contacts, welcome to the system (at least Android has this function, it can have contacts from many sources like Skype, FB, WhatsApp, GMail, and can put all of them under 1 person in the Contacts app).

I wonder if the linking is even necessary, if FBs dark pattern made your friends upload their contact list, they could just infer that since Alice and Bob are your FB friends and they both have your name and number on their uploaded contacts, they can probably associate that number with your FB profile with x% certainty (a higher percentage if your FB friends Cedric, Dave, Emily and Fritz also have the same name and number...).

Fun stuff huh? /s Someone should associate that Patrick Stewart "Extras" line "But it's too late, I've seen everything." with Mr. Zuckhole.

> And if a friend had put your name and phone number in their phone, and they synced their contact list with FB and merged the contacts, welcome to the system...

> I wonder if the linking is even necessary, if FBs dark pattern made your friends upload their contact list, they could just infer that since Alice and Bob are your FB friends and they both have your name and number on their uploaded contacts, they can probably associate that number with your FB profile with x% certainty (a higher percentage if your FB friends Cedric, Dave, Emily and Fritz also have the same name and number...).

Yeah, my bet's on this. Once, long ago, when I was more trusting, I installed the Facebook app on my phone (back when Android permissions were all or nothing). Facebook slurped up my address book, and I don't even think they ever explicitly asked for permission to do that.

About six months to a year ago I noticed these contacts in my FB data dump...and they were connected to all kinds email addresses and phone numbers I never had in my address book.

My guess is that if you want to keep Facebook from linking to your personal info from other sources, you need to have zero data overlap (different email, phone, name) and never install any of their apps on any device you own and never share a browser session between Facebook and any other browsing.

I was thinking the same thing too. You have to be super deligent and careful NOT to be a part of FBs data collection campaign (or any other company trying to harvest data the same way). This does not sound morally right.

Probably best to have no Facebook friends also.

I started tracking the advertisers who upload my contact information a few months ago. One day I "hid" all of the pages in that section of the ads settings page and the next day it showed that over 100 pages had uploaded my contacts. I messaged a selection of the "new" pages (I'm not sure if they were actually new or if the had just re-upped their list). Most of them responded that they were confused as to how my info would end up associated with their pages, since most or all of them are quite a distance from where I live. A couple mentioned that they outsource their marketing to outside groups. My theory is that there may be industry marketing groups that collect contact information for use in social media advertising.

One auto dealer worker responded to my question, "how did my name get on a list that your page uploaded?" by saying "I don't know, I just post ads."

The ad settings page suggests that usually the uploaded identifying information is a phone number or email address, but the wording is vague enough that it could probably be just about anything. So if you've ever shared your phone number with Facebook (even once, I suspect, even if you've since deleted it) I wouldn't be surprised if they use that to identify you. Similarly, a postal address or even a city might enough to identify you for these purposes.

Edit: A quick Google shows a number of groups similar to [1] that sell lists of auto owners. I would be surprised if there were not similar groups for other industries, particularly real estate.

[1] https://hedgescompany.com/consumer-automotive-mailing-lists/

Mine is almost entirely car dealerships (in the US, which I am not in).I have never bought a car, much less at a dealership.

Mine is exclusively car dealerships. Are DMV records public?

Speculation elsewhere (a Twitter thread I've since lost) is that car dealerships are simply uploading every possible US phone number as a "contact". It seems reasonable, and I can't really think of other reasons car dealerships in states I've never visited have added me (or at least some info Facebook associates with me) as an ad target.

Why would this help them? Facebook already lets you target by geography, they could just target all US residents much more easily.

Advertisers want more control over who they target than just geographic regions. I'd bet that Facebook let's you select demographic targeting using all of the information they hold on your contacts, so by uploading every phone number you can target people based on geography, age, income, family size, etc.

But you can't target demos for users not in your contacts? That makes no sense.

Yes. That's why when you buy a new car there is a flood of 3rd party warranty snail mail spam.

(NB: There are very valid reasons WHY this information is in the public record...mostly to make it harder to fence stolen vehicles.)

Either that, or the DMV sells them. (I use one-off e-mail addresses, and [email protected] is _really_ popular)

Absolutely DMV sells everything on you. State I live winter time - Florida - when I got speeding ticket, less than 4 days later my mailbox was full of ticket schools’ solicitations. They knew everything about me and my ticket. They even knew time and street and speed I was pulled over and cleverly used that in marketing titles: “clocked 67 in 40 miles with highschool on the corner of Oak and Main St? withiut knowledgeable attorney that can cost you 90 days in county jail. Call now”. Its even worse - a friend also in Florida had DUI. Day three a lawyer knocks on his door bringing pizza and beers (!) to sit down discuss his case for free evaluation! Totally unsolicited knock at his door.

That’s not the DMV selling anything, it’s the clerk of court...everyday they publish a list of new cases (public record) and your ticket is attached to the case and the ticket contains all relevant data (name, address, license #, dob, charge, etc...) and an added bonus the court will also link your dmv driving record to the ticket case so the “scrapers” get your dmv record anyway (for free). They do the same for foreclosure cases.

Same here. I think they upload your address and the fact that you have a car and then attempt to sell you another car based on those two factors (as well as age and gender).

Mine is about 70% US car dealerships and I'm not American. I guess they've been buying up some low quality contact lists

How do you even get the number? It doesn't list the total on my page and I couldn't even get to the end of the list after clicking "See More" for 10 minutes...

Mine is zero. I wonder if maybe its not showing for me since I'm in Canada