Avis Budget has filed papers with US regulators for approval of a possible deal to purchase Dollar Thrifty. The car hire giant is looking for a green light from the antitrust agency to ensure that any possible purchase will not violate US antitrust laws. Dollar Thrifty Automotive Group has been at the centre of the car hire world recently as both Avis and rival Hertz have made gestures to purchase the number four rental car in the US.

While both companies have shown interest in Dollar Thrifty, both Avis Budget and Hertz Global Holdings Inc have significant antitrust hurdles to overcome before any merger takes place. Antitrust experts say that Hertz has a slight advantage since it is mainly a business traveller car hire firm, while if Avis takes control of Dollar Thrifty, it will put a stranglehold on its already strong leisure car hire market share.

Hertz made its original proposal to purchase Dollar Thrifty on 26 April, and the following week Avis Budget showed its interest in purchasing the company after two Dollar Thrifty shareholders claimed the offer was far below market value. The two car hire firms have since manoeuvred back and forth in their attempts to finalise a deal, causing significant trade movement on the NYSE. Dollar Thrifty closed at $49.42, Avis at $13.50, and Hertz at $12.93 on Thursday.