Her staff fielded close to 900 regulatory inquiries last year, nearly four times as many as five years ago.

Tenet, already the subject of numerous regulatory inquiries regarding its more recent billing practices, disputed the government's claims.

Amy S. Hughes, the spokeswoman for the company, declined to comment further on the nature of the regulatory inquiry.

Her practice specializes in white-collar criminal defense, regulatory inquiries, and legislative advocacy.

The bank eventually paid more than $4.65 billion to settle regulatory inquiries and class-action lawsuits.

Deeper knowledge of regulatory law and the ability to respond to a regulatory inquiry or enforcement action.

Mr. Ortiz said he was not aware of any specific regulatory inquiries focused on Olde.

Potential arbitrators must also disclose whether an investor has sued them or whether they have been subjected to regulatory inquiry.

More serious accounting problems may yet emerge, and the company has already been forced to consider outsized financial restatements as a result of the regulatory inquiry.

A regulatory inquiry would not be the only gantlet US Airways would have to run.