Chelsea have been fined €10 million (around £8.57m) by UEFA for breaching Financial Fair Play rules after "submitting incomplete financial information".
The Blues have spent around £600m on 19 new players since the arrival of new owner Todd Boehly in May 2022.
However, this fine corresponds to a seven-year period under previous owner Roman Abramovich.
"Following the club's sale in May 2022, the new ownership identified, and proactively reported to UEFA, instances of potentially incomplete financial reporting under the club's previous ownership," European football's governing body said in a statment on Friday.
Juventus have also been fined €10m (£8.57m) for irregularities in their transfer dealings, which saw the Bianconeri docked 10 points in Serie A last season.
The Italian giants will be forced to pay double that amount if their financial records for the next three years fail to comply with regulations.
Juve have also lost their place in the Europa Conference League for the coming season and will be replaced by Fiorentina in the continent's third-tier competition.
"We regret the decision of the UEFA. We do not share the interpretation that has been given of our defence, and we remain firmly convinced of the legitimacy of our actions and the validity of our arguments," Juventus president Gianluca Ferrero said.
"However, we have decided not to appeal this judgement."