BP says its special investigative unit is looking into several hundred claims for compensation after the oil disaster in the Gulf of Mexico, to try to prevent cases of fraud.
Fishermen in Louisiana need a commercial fishing licence before claiming any money from the company.
The state's Wildlife and Fisheries Department has issued 22,000 more licences since the leak than it did in the same period last year.
But the BBC reports, fishermen are concerned that some of this money is ending up in the wrong hands.
BP says about 10% of claims after any major incident, are likely to be false.
The company has already paid more than $US300 million from its total compensation fund of $US20 billion.
The leak began on 20 April after an explosion and fire on the Deepwater Explorer oil rig. it was finally stopped on 15 July.