Backstreet Boys were managed by Lou Pearlman
The mother of two members of a failed boy band had complained Lou Pearlman and his Trans Continental Entertainment company had violated strict laws.
Merrily Goodell said two of her young sons were made to work past 2330 when they were part of the band Take 5.
But the Florida Department of Labor said their was no evidence of any laws being broken.
Kenneth Williams, an administrator in the department's Office of Compliance and Enforcement, wrote to Mr Pearlman on Thursday to tell him the allegations were unproven.
The letter said all investigations had now been terminated and the file closed on the case.
"I'm happy to say that we are vindicated, as expected, from all allegations," Mr Pearlman said.
Mr Pearlman has become something of a celebrity in his own right after the success of the TV show Making the Band.
The series, which was shown on Channel 4 in the UK, put together boy band O-Town after auditions were held around the US.
Protegés
The band has since gone on to score hits in both the US and UK and a second series of the programme charted their rise to fame and a third has been commissioned.
But all was not well between the band and their management company and at the end of series two, O-Town split from Trans Continental and signed to a new label.
It is not the first time Mr Pearlman has seen his protégés dump him.
In 1999 he sued the members of 'N Sync after they quit his label.
An out-of-court settlement was reached which allowed the band to keep their name, which Mr Pearlman claimed to own.