The U.S. Department of Justice closed a corruption investigation into a U.K.-based seismological company this week, citing the firm’s cooperation with the probe and the help it provided in the prosecution of a South Korean official who was convicted last year of laundering bribes.

The company, Guralp Systems Ltd., represented by Miller & Chevalier, had been under investigation for violations of the Foreign Corrupt Practices Act over past payments to Heon-Cheol Chi, the director of a South Korean earthquake research center.