A shareholder took a legal action against the Directors of Chicago based General Growth Properties Inc. He alleged that they shouldn't have declined a $10 billion buyout offer from Simon Property Group Inc (based in Indianapolis), who is its opponent.

Six board members along with Chairman John Bucksbaum were blamed of violating their duty to the bankrupt mall operator's investors for not accepting Simon's bid. The bid was made public on Feb. 16, under which shareholders were to get about $9 a share, including $6 in cash.

According to General Growth, the price was low and that it would invite other buyers to make bids.

"This conduct is substantially unfair to GGP and the company's public shareholders", investor James Young said in his complaint brought on behalf of stockholders and for the benefit of the company.

James is looking for a court order which stops the Directors from entering into any contract that is harmful either for the company or for its shareholders. It should also not make it more difficult or expensive for a customer to buy it.

The world's largest private-equity firm, Blackstone Group LP may join Simon's bid. The negotiations are not made public because the Blackstone Group is only in introduction talks with Simon.