An investor in Rice Energy Inc. on Wednesday sued in Delaware federal court to halt the oil and gas driller's planned $6.7 billion sale to EQT Corp., saying shareholders do not have enough information to vote on a deal that would create one of the top shale energy producers in Western Pennsylvania.

In the proposed class action, Patrick Gordon accused Rice of misleading stockholders last month in a filing with the U.S. Securities and Exchange Commission related to the stock-and-cash merger. The filing, he said, lacked important details regarding the company's financial projections and the valuation analyses its financial adviser, Barclays Capital Inc., used in crafting its fairness opinion.

The deal, announced June 19, would expand EQT's acreage in Pennsylvania's Washington and Greene counties, where the companies have vied for drilling dominance. In exchange, Rice investors would receive $27.04 in cash and stock for each share they held in the Canonsburg, Pennsylvania-based producer.