Google doesn’t sell their private data collection. They use it to target ads so it’s the most valuable thing they have (or as they would call it their “unfair advantage”), so selling it directly is out of question. There are multiple data brokers that also have very comprehensive lists that will happily sell it to anyone.
Google has that list, and it’s for sale. Regardless if you tell them, they know.
Google doesn’t sell their private data collection. They use it to target ads so it’s the most valuable thing they have (or as they would call it their “unfair advantage”), so selling it directly is out of question. There are multiple data brokers that also have very comprehensive lists that will happily sell it to anyone.
They sell the targeting, from there it’s simple for the advertisers to compile the list with the tracking cookies left behind.