"Sentry Legal has not been 'raided' by the FBI," said spokesman David Yancey, who said the firm had contacted the FBI and U.S. Attorney's Office and pledged cooperation.
Officers involved in the raid were from the FBI, IRS and Office of the Special Inspector General for the Troubled Asset Relief Program, as well as local agencies.
No further details were available and the search warrant was sealed, the U.S. attorney's office said.
CC Brown was operated by attorney Charles Craig Brown, but the Better Business Bureau reports he had retired.
The Utah State Bar directory lists Brown as a 1974 graduate of the University of Utah law school, but it says his law license was on "disability" status.
Brown could not be reached Tuesday afternoon for comment.
The Utah BBB gave CC Brown an "F" grade, citing the 55 complaints against it.
State documents show that CC Brown took up-front fees from consumers who were having trouble paying their mortgages in return for helping obtain modifications.
Last year, the Maryland Commission of Financial Regulation issued a cease-and-desist order against CC Brown Law and Charles Brown, allegedly for violations of that state's laws that included offering unlicensed credit services.
A Maryland resident who was in default on his mortgage told the commissioner's office he paid $549 in fees to CC Brown but no modification was completed and a request for a refund was not honored, according to the order.
It accuses the law office of making false or misleading statements to consumers.
In Utah, the state Division of Real Estate issued a cease-and-desist order in 2010, accusing Brown and his law office of operating without a mortgage license. Brown agreed to settle the allegations with a $5,000 fine and to discontinue negotiating loan modifications without a license.
Information for consumers
People who have been working with the raided businesses on mortgage modifications and might want to submit documents to the FBI or get more information can call 1-877-236-8947 (press option 2, then option 3).