Hertz's shareholders include Larry Robbins' Glenview Capital Management and Daniel Loeb's Third Point Capital.
Third Point had a stake of about 1.3 percent in Hertz as of March 31, while Glenview had about 3 percent.
Hertz said in May that it had identified errors relating to prior periods that could require it to restate 2011 results.
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The company had said then that the restatement would likely reduce its 2011 net income by as much as about $10 million, to $174 million.
Hertz's accounting problems come at a time when the car rental industry is picking up as business and leisure travel increases along with an improving economy in the United States.
However, Hertz has not been able to benefit, partly due to higher expenses. The company's net earnings fell 13 percent in the fourth quarter ended Dec. 31.
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Hertz said in March that during the quarter, it had identified errors totaling $46.3 million in prior periods.
The company, under pressure from investors to focus on car rentals, said in March that it would spin off its equipment rental business, raising $2.5 billion to reduce debt and fund a $1 billion share buyback.
Hertz operates in a consolidated market, along with Avis Budget and privately held Enterprise, which together control about 90 percent of the U.S. car rental market.