Manchester City have been given a two-year academy transfer ban, with the second year suspended, and fined £300,000 for the "tapping up" of two youngsters.
In a statement, the Premier League said City would be prohibited from signing any academy players registered with a Premier League or Football League club in the preceding 18 months.
The rule breaches relate to the signing of an 11-year-old from Everton and a 15-year-old from Wolverhampton Wanderers.
The statement said: "The Premier League has sanctioned Manchester City FC for breaches of its youth development rules.
"The breaches concern approaches to two separate academy players whilst they were each registered with another club.
"Following an investigation, the Premier League found evidence that the club's conduct prior to applying to register the players contravened league rules.
"This included evidence of contact between the club and members of each academy player's family while those academy players were still registered with their previous clubs."
The statement said City "will be prohibited from registering any academy players in the under-10 to under-18 age range who have been registered with a Premier League or EFL club in the preceding 18 months."
It added: "This ban will last for two years. The period of this ban from 30 June 2018 onwards will be suspended for three years to be activated in the event of any similar breach by the club.
"In each case, the academy player was conditionally registered with Manchester City while the Premier League's investigation was ongoing.
"As a result of the club's breaches, the players' registrations will be terminated on a specified date, with no compensation rights retained by the club, and the club will not be permitted to re-register them as academy players.
"In addition, Manchester City have offered to pay compensation to each player's previous club and maintain educational provision for each player until the completion of his GCSEs."
Manchester City have refused to comment on the ban and fine.
In April, Liverpool were fined £100,000 and given a two-year academy transfer ban, the second year of which was also suspended, for the "tapping up" of a Stoke youngster.
That case involved the use of forbidden inducements, which is not the case with City.