Russia’s largest mobile network operator, Mobile TeleSystems, has agreed to pay $850 million to settle a corruption case that highlights the importance of having effective internal accounting controls.

MTS allegedly violated the Foreign Corrupt Practices Act by paying at least $420 million in bribes from 2004 to 2012 to Gulnara Karimova, the 46-year-old daughter of ex-Uzbekistan President Islam Karimov, who died in 2016. Karimova also was a Uzbek official who held sway over the country’s telecom operations.