GT Advanced, which supplied sapphire to Apple Inc, filed for Chapter 11 protection this month under mysterious circumstances, sending shares plummeting.

The case boggled the minds of market analysts when GT refused to explain why it had imploded, citing confidentiality clauses in its Apple contracts.

While shareholders are typically wiped out in bankruptcy, GT Advanced stockholders believe their equity may not be worthless. Some are reaching out to the U.S. Department of Justice's bankruptcy regulator, the U.S. Trustee Program, asking it to form a committee in GT's bankruptcy to represent shareholder interests.

According to a source close to the effort, law firm Brown Rudnick, which routinely represents creditors in big Chapter 11 cases, is drafting a letter to the Trustee on behalf of a shareholder group requesting a committee.

Other shareholders, like Nathan Cottrell, are working independently. Cottrell, a Philadelphia-based IT salesman, told Reuters he's reached out to the Trustee's office to request a committee and been in touch with law firms about representation.

GT has "a lot of other product lines that are about to start firing up," Cottrell said in an interview on Thursday. "I believe there's value for equity."

The odds may not be in shareholders' favor. Official creditors' committees, appointed by the Trustee and paid for by the debtor, are only formed when the Trustee feels the creditor group in question has a decent shot at recovery.

Since stockholders of bankrupt companies are usually out of the money, equity committees are rare, and shareholders tend not to have a unified voice in Chapter 11 cases.

The company's stock no longer trades on the Nasdaq, but still trades over the counter at a price that currently values GT at $72 million, according to Thomson Reuters data.

Early in GT's case, company attorney Luc Despins said GT "feels terrible" about the loss to shareholders and "will work every day to recover that value."

The Trustee has yet to make a decision on an equity committee, and a spokeswoman for the office declined to comment on Thursday. Despins, meanwhile, did not return a call seeking comment.

One reason for lingering uncertainty over equity value may be the refusal by GT to disclose the specifics of its downfall, which has drawn the ire of creditors and regulators, the Trustee included.

GT has said it plans to shut down key sapphire operations in Mesa, Arizona, laying off hundreds and reorganizing around a smaller business.

Creditors are hoping for some clarity on the company's financial picture in the coming days, when GT has said it will file a proposed settlement agreement with Apple that may detail its collapse.

Shareholders this month sued the company's officers and directors, accusing them of providing misleading information about stock and bond offerings.

(Reporting by Nick Brown; editing by Andrew Hay)

By Nick Brown