Freetrade nominees limited and drivewealth are the companies who hold freetrade customer shares.
212 don’t have a nominee company in the UK (note it is standard practice and a requirement unless you opt out that shares are held in a nominee). They have in the past tried to claim the IB hold your shares but this would be highly unusual and likely incorrect. IB don’t normally hold customer shares and it would be unusual for them to break that practice, IB nominees limited hold IB customers shares.
212s terms and conditions state that a nominee, third party or 212 themselves may hold your shares, but when questioned will not tell you who actually has your shares. Note that for 212 to hold your shares you must opt out of the requirement that brokers use use a nominee company. It’s not clear is accepting the terms and conditions is enough for that but that seems like it might be the case.
The only claim 212 have ever made is that IB hold your shares, which not only seems to go against what their terms and conditions say, but also doesn’t add up, as IB wouldn’t take on the high risk of holding a startups customers shares directly under their broker company rather than in a nominee company as they’re required to do.
End result is that the terms are unfavourable to the customer, and the location of your shares is still questionable.
For a bit of fun (if you can call it that) almost all brokers have a nominee company in the UK. You can look them all up, just not 212 as they don’t seem to have one