As MCI's largest customer, the government provides the company with $700 million to $1 billion in business annually.
Fleming sought protection from creditors in April after losing a contract with its largest customer, the Kmart Corporation.
He helped salvage a contract for F-14 fighters last year and repaired the company's relationship with its largest customer, the Navy.
Oakley has been searching for new outlets for its products after the Luxottica Group, the parent of its largest customer, the Sunglass Hut retail chain, opted not to stock new sunglasses from the company.
For years, Barry Goldman, president of the Bancroft Cap Company in Cabot, Ark., would hear rumors that his largest customer, the United States military, was planning to sharply increase its order for the wool berets his company makes.
Although investors will welcome new business from BAE's largest customer, the group has signalled its determination to move into new territories and new markets with its failed attempt to merge with EADS, the owner of aerospace giant Airbus.
After its largest customer, the New York Trap Rock Corporation, a producer of crushed stone, bought Cornell in 1958, Mr. Spangenberger remained in charge of the towing operations, which continued to be called Cornell Steamboat.
Royal Mail has lost a crucial contract with its second largest customer, the online retailer Amazon, as a wave of strikes threaten parcel deliveries in the busy pre-Christmas sales period.
But two of its large customers, the insurers Cigna and PacifiCare Health Systems, were threatening to steer their members to a much cheaper competitor, Allegra, unless Schering-Plough lowered Claritin's price.
