Six companies are expected to make binding offers for storied Hollywood studio Metro-Goldwyn-Mayer  by a newly set March 19 deadline, a source familiar with the situation said on Tuesday.

Those expected to participate in the new round of bidding include Time Warner, Lions Gate, Liberty Media Corp, Access Industries, a company controlled by industrialist Len Blavatnik, and Elliott Management, according to two sources close to the deals.

Several of them had been involved in an earlier round of non-binding bids that went as high as $1.7 billion. It was unclear who the sixth party was, they added.

News Corp, which had been interested, has pulled out of the process. Summit Entertainment, home to the Twilight franchise, has remained on the sidelines throughout the process and was undecided on whether to put in an offer, one of the sources told Reuters.

The source said Qualia Capital has also been waiting in the wings with a plan to restructure some of MGM's debt into equity, and then infuse cash into the company to keep it running as a going concern if a sale does not transpire.

Bidders, after looking over the books and assets including MGM's film library of mostly older gems like the James Bond and Pink Panther franchises, are unlikely to put in second round offers above $1.5 billion, the sources said.

MGM, Time Warner, Lions Gate, Summit and Liberty Media all declined comment or were not immediately available.

Once-thriving studio MGM owns a piece of two Hobbit films to be produced by Lord of the Rings director Peter Jackson, but its attraction lies partly in its library of more than 4,000 film titles.

MGM, which enlisted turnaround specialist Stephen Cooper last year to help it restructure, got saddled with the debt from a 2005 buyout. The studio said in November it was exploring a sale, receiving tentative interest from rival media companies as well as buyout shops.

If the current round of bids comes in too low, MGM's creditors could decide to keep and restructure the studio, possibly filing for pre-packaged Chapter 11 bankruptcy reorganization, sources say.

MGM is owned by a group including private equity firms TPG, Providence Equity Partners, DLJ Merchant Banking Partners and Quadrangle Group, and media companies Sony Corp and Comcast Corp.

Analysts say Time Warner might be in the best position to acquire MGM as its film library would fit well with its Warner Bros. catalog.

(Reporting by Sue Zeidler; Editing by Edwin Chan and Steve Orlofsky)