Yet in clearing P.S.G., at least for now, UEFA may have given new ammunition to those who have criticized its commitment to the rules, which were introduced to stop spiraling debts among many clubs and to prevent an arms race among superrich club owners. One such critic, Javier Tebas, the Spanish league president, declared financial fair play “dead.”

“It has no value,” Tebas said.

In Italy, the decision to clear P.S.G. was contrasted with the treatment of A.C. Milan, the Italian club that received a one-season ban from European competition after a similar investigation. Critics were quick to note that P.S.G., which has won five of the past six French titles, including the most recent one, shares its owner with BeIN Sports, the Qatari-backed sports network that is UEFA’s biggest television-rights buyer.

Given the backlash, as well as tensions within the investigations group itself — some members did not agree with clearing P.S.G. — the chairman of the body overseeing the financial fair play rules is considering reviewing the decision, according to people familiar with the board’s plans.

UEFA declined to comment.

At the heart of the P.S.G. case is a set of sponsorship agreements valued by the club at more than $200 million a season with companies and organizations linked to Qatar. UEFA’s investigators found P.S.G. was receiving far more for the deals than it would for similar ones on the open market.

One such agreement, a nine-figure deal with the Qatar Tourism Authority — by far the club’s biggest sponsor — was reduced by well over half in UEFA’s most recent accounting of the club’s balance sheet. That calculation has been a source of frustration for P.S.G., which agreed to be punished for violations of financial fair play rules in 2014 in a settlement that increased the valuation for the Q.T.A. deal.