Last November, RBS Group — the parent company of RBS WorldPay, which handles ATM processing for ATM Network — received financial help from the British government. As part of the agreement, RBS Group agreed to divest itself of RBS WorldPay.

Now the new owners have been found, and the sale finalized.

Royal Bank of Scotland Group Plc, the U.K.’s biggest government-owned bank, agreed to sell its credit- card payment processing unit to Advent International Corp. and Bain Capital LLC for 1.7 billion pounds ($2.7 billion).

RBS may receive a further 200 million pounds if the buyers’ returns hit certain targets, the Edinburgh-based bank said in a statement today. RBS will keep a 20 percent stake. It will also book a gain from the sale of about 850 million pounds after goodwill, separation and transaction costs, the bank said.

RBS is being forced to dispose of the unit to comply with European Union state-aid rules after taking 45.5 billion pounds in a taxpayer-funded rescue during the financial crisis. The bank announced this week the sale of 318 branches to Banco Santander SA to comply with the ruling, and must also dispose of its insurance division.

Advent and Bain Capital are private-equity firms. Such firms typically buy distressed companies, operate them for several years, then sell them at a profit.

But they also will operate profitable businesses on occasion, and that appears to be the case here. RBS has been steadily profitable, reporting $400 million in profits last year, and Advent and Bain appear to regard it as a good place to park investment money while the world recovers from global recession.

Advent also owns a 51 percent stake in another payment process, Fifth Third Processing Solutions, but said there are no plans to combine the processing companies.

The companies anticipate no changes in day-to-day operations, and the ownership change shouldn’t even be noticeable to ATM owners. If changes crop up in the future, ATM Network will notify ATM owners and help them adjust.