Pedestrians are reflected in a window as they walk by a sign displaying mortgage rates inside a Bank of America office on June 7, 2012 in San Francisco, California. In a corruption survey released this week, Transparency International called for banks and other U.S. financial services companies to increase openness. - 

Jeff Horwich: Big business is not doing enough to crack down on corruption. That's the conclusion of a new report by the anti-corruption watchdog Transparency International. The report slams the usual suspects: companies from China and Russia, but it's not happy about some American corporations either.

In London, Marketplace's Stephen Beard reports. 

Stephen Beard: Transparency -- as its names suggests -- believes that openness is the first step toward cleaning up business and eliminating corruption. The watchdog has put 105 of the world's biggest corporations to the test, and then ranked them as to how open they are about their own affairs.

An oil company came top: Statoil of Norway. The Bank of China came bottom. No surprise there. In another index last year Chinese companies were ranked among the most likely to offer a bribe.

But, says Transparency's Karen Egger, at least China's trying to improve.

Karen Egger: China has recently amended its criminal code to introduce foreign bribery as an offense and we welcome that.

Much of the global drive against corruption has been powered by the U.S. government, but Transparency says the performance of American corporations in this index is generally not good. The U.S. was dragged down by its financial sector. Goldman Sachs and Bank of America were among the low scoring companies.

In London, I'm Stephen Beard for Marketplace.