The University of San Diego is suing seven rental car companies, claiming they colluded to fix prices.
The university's Center for Public Interest Law says Budget, Hertz, Avis, Dollar, Enterprise, National and Alamo are exploiting a 2006 California law that allows them to exclude a mandatory airport fee from their advertised base rates.
In return, the law requires the companies to set aside $24 million for state tourism.
A study by students at the university shows that while the companies are no longer counting the airport fee in their base rates, they have not reduced the price of a car rental to reflect the discount.
They also added a 2.5 percent surcharge to come up with the money for the tourism account, the center says.
A spokeswoman for Enterprise says the case is meritless. The other companies declined comment.
Information from: The Sacramento Bee, http://www.sacbee.com
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