We met with a financier who has helped raise capital for a host of Chinese businesses and arranged for a number of them to be listed on American exchanges.

FORBES: Reading China's Mixed Signals

Those certifications or audit opinions are required by law for public companies to be listed on most global exchanges.

FORBES: Is Any Other Audit Firm Vulnerable Besides Ernst & Young?

By dint of being listed on international exchanges, they have some motivation to be transparent to outside shareholders.

FORBES: The Government Oil Play

The DRs can be listed on stock exchanges anywhere in the world and are issued to raise capital in IPOs, follow-ons and rights offerings.

FORBES: Samsonite's IPO Pick of Hong Kong Over NYSE Not Unique