But former KBR parent Halliburton Co (HAL.N) said last month it would pay $559 million to end the investigation if the government approved the settlement, which was the largest penalty against a U.S. company for bribery charges under federal law.
The bribes were paid between 1994 and 2004 to secure four contracts for a KBR joint venture to build and expand Nigeria's Bonny Island liquefied natural gas terminal, according to the government.
KBR Inc was charged with five counts, including conspiracy to violate the Foreign Corrupt Practices Act (FCPA).
A truly multinational scheme, it involved partner companies from Italy, France and Japan, and huge sums of money wired through banks in Amsterdam and New York to accounts in Monaco and Switzerland.
KBR also used shell companies in Portugal, referred to by the government as Madeira Companies 1, 2 and 3, in an effort to avoid breaking the FCPA law, the government said.
"KBR avoided placing U.S. citizens on the board of managers of Madeira Company 3 as a further part of KBR's intentional effort to insulate itself from FCPA liability," according to the government prosecutors' filing with the U.S. District Court for the Southern District of Texas.
Albert "Jack" Stanley, a former KBR chief executive, pleaded guilty last September to charges stemming from the Nigeria bribes and agreed to cooperate with investigators.
KBR declined to make any further comment late on Friday. (Reporting by Braden Reddall; Editing by Bernard Orr)