CW Government Travel (Carlson) sued the government over modifications to a travel services contract (DTS DTR-6) that was awarded to Northrop Grumman. The court dismissed Carlson's challenge because Carlson was not a bidder or prospective offeror on the contract—meaning it had no legal standing to protest the modifications. This case shows that only companies directly competing for a contract can challenge how it's modified or awarded.
You must be an actual bidder or prospective bidder on a contract to legally challenge its modifications. Simply being in the same industry isn't enough.