The court ruled that allowing them to claw back funds from shareholders would set a damaging precedent for the securities markets.
The maker of alternative fuel-storage tanks for the trucking industry is seeking a buyer through the bankruptcy process.
Facebook co-founder Eduardo Saverin has offered $22.7 million to buy the company, which has been struggling to raise funding.
The end-of-life care provider has until April 30 to complete the sale of its money-losing operations in seven states.
The Denver company says the declining price of oil and the closure of a key pipeline "continue to be serious problems."
The suits seek to resolve a dispute between the insolvent retailer and its consignment vendors over $85 million worth of goods on its shelves.
The call-center software company plans to execute a restructuring that would eliminate $320 million in debt and equitize another $60 million.
The operator of HomeTown Buffet and other chains says an $11.3 million court award in a food poisoning case prompted the bankruptcy filing.
The retailer plans to close 30% of its stores as it slims down to cope with increased competition and substantial debt.
The short-haul carrier says bankruptcy will allow it to renegotiate agreements with the larger airlines for which it provides regional flights.