The Premier League has confirmed Manchester City have been found guilty of all charges of breaching its financial rules over a nine-year period, with the club found to have boosted their income by a staggering amount of more than £900m.

In a bombshell announcement the Premier League revealed an independent commission had found City guilty of arranging “sham ­contracts” with commercial partners to artificially inflate revenues and reduce costs, and of filing inaccurate accounts to hide the true state of their finances, which if accurately reported would have led to significant breaches of Premier League and Uefa spending limits.

The club were also found to have entered into “sham” image rights deals with players and the then manager Roberto Mancini to artificially inflate their earnings.

City have said they will appeal by Friday’s deadline “on the basis that the opinion contains clear material errors, of law, principle and fact, and is unsafe”. Their chief executive, ­Ferran Soriano, said in a video sent to employees that the decision was based on a “Premier League conspiracy theory”.

The appeal is expected to run alongside a sanctions hearing presided over by the independent commission, with the Premier League eager to conclude matters as quickly as possible.

The extraordinary scale of what Hull’s owner, Acun Ilicali, has described as City’s “financial doping” has sent shock waves throughout the world of ­football, leaving executives at other Premier League clubs stunned.

The Premier League’s chief ­executive, Richard Masters, described the case “as the most significant in Premier League history”. It seems inevitable it will lead to an unprecedented punishment, including in all probability a points deduction that will condemn City to relegation.

Although there is no direct precedent given the scale of City’s offences, Everton’s 10-point penalty for breaching profitability and sustainability rules by £19.5m over a period ending with the 2021-22 season was based on a Premier League tariff of six points for the initial breach, plus an additional point for every £5m the club overspent.

The commission made damning comments regarding the behaviour of City witnesses during the hearings. “Evidence given by a number of important factual witnesses called to give evidence on behalf of the club was false in a number of key respects,” it wrote, arguing that some witnesses had given evidence “they knew to be untrue and so had been dishonest”.

Graphic showing Manchester City’s ‘sham’ commercial deals

City were found to have operated a “disguised funding scheme” worth £830.6m over nine seasons, from 2009-10 to 2017-18, and to have hidden costs by a further £70m. In addition the club have been found guilty of multiple breaches of failing to cooperate with the Premier League and act in good faith. The commission concluded the club had made concerted efforts to stop and frustrate the investigation.

The Premier League published a redacted 40-page “core decision” from the independent commission, which has taken almost two years to produce after a 42-day hearing that concluded in December 2024.

The league said: “The independent commission found City arranged ‘sham’ commercial deals with a number of its sponsors during the period, which were part of a disguised funding scheme, whereby those companies were only required to pay a portion of the relevant sponsorship fees. The remainder was funded by Abu Dhabi United Group Investment & Development Ltd (ADUG), which owned the club.

Manchester City chief executive Ferran Soriano leaving the European Football Clubs board meeting in Copenhagen. Photograph: PA Video/PA

“As part of the scheme, further ‘sham’ arrangements, funded by ADUG, were entered into to enable the club to record lower operating expenses than it actually incurred, as well as a ‘sham’ circular arrangement with Fordham, an entity that purchased the club’s players’ image rights, that was funded by ADUG.

“The purpose of these schemes was found to have been to artificially inflate the club’s revenues, and reduce its costs, by more than £900m during the affected period, to appear to comply with financial rules.

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“The consequence of this, as the commission found, was that the club filed misstated accounts and concealed the true state of its finances from its auditors and football regulators.”

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ADUG bought City on behalf of Sheikh Mansour bin Zayed al-Nahyan for £200m in 2008, with the new owners making an immediate impact by paying £32.5m to sign the Brazilian superstar Robinho from Real Madrid. That was the start of a spending spree City struggled to afford from their existing revenues, with the independent commission concluding that the only way to match the owners’ ambitions for the club was for ADUG to “provide very significant funds by way of equity contribution”.

The commission report states that in 2010 City devised a scheme whereby sponsors would pay a “base sum” and ADUG would pay a “tagged sum”, despite the base sum being the only true revenue. The recorded sponsorship fee would be the total of them both.

City’s lawyers claimed that the “tagged sum” was a loan by the Abu Dhabi government on liabilities on sponsorship fees. The commission rejected that argument.

The judgment is a huge victory for the Premier League and Masters. Despite the commission demonstrating that City breached Uefa’s spending limits there appears little prospect of Uefa’s case being revisited because there is a five-year statute of limitations on its disciplinary proceedings. Uefa’s punishment of City in relation to alleged financial fair play breaches was largely overturned in 2020 by the court of arbitration for sport, which found “most of the alleged breaches were either not established or time-barred”.

Masters said: “The core decision establishes the facts of what happened at Manchester City during this period. It details how the club systematically broke Premier League rules for nearly a decade. It also vindicates the Premier League’s decision to pursue this case against Manchester City.”

He said in relation to sanctions: “Now we have the commission’s decision, we are committed to moving swiftly through the remainder of the process, to provide certainty for the league, our clubs and fans.”

Other Premier League clubs are surprised City have not reached an agreed sanction with the Premier League, given the judgment, but City continue to deny wrongdoing. “Manchester City FC is both disappointed and surprised by the opinion of the Premier League commission, that has been published today,” the club said. “The club is innocent of the accusations made by the Premier League and a comprehensive body of irrefutable evidence exists in support of all of its positions, relating to this case. The club will therefore be relentless, and where necessary proactive, in any and all appropriate regulatory and legal forums.”