Liverpool have been done for tapping up a schoolboy from Stoke and banned from signing Academy players for 2 years (plus a fine):

https://www.theguardian.com/football...rs-fined-stoke

Liverpool, who accept the sanction, have been found guilty of speaking to the player and/or his family prematurely and of offering inducements....

I have no evidence at all, but I suspect this is common practice by the big clubs. Liverpool made the mistake of getting caught.