The European Commission said on Thursday that it had reached a settlement with Gazprom, finally concluding a long-running antitrust investigation into the Russian energy giant’s dominance in regional gas markets.

Officials in Brussels said the company had accepted a series of concessions, but unlike with competition inquiries into other companies like Google and Intel, it declined to issue any financial penalties. That provoked criticism in countries like Poland, which say they have been squeezed by the energy company in the past, and fear that the deal between Gazprom and the European Commission does not go far enough to prevent similar behavior in the future.

Still, the settlement could mark the end of a long legal tangle between the commission, the European Union’s executive arm, and the Russian state-controlled company, which is the dominant supplier of natural gas in parts of Europe.

The commission had originally filed charges against Gazprom in 2015, accusing it of breaking the bloc’s antitrust rules, leading to higher gas prices in five Central and Eastern European countries, including Bulgaria and Poland. Last year, it accepted provisional commitments by the company to address those charges.