A gift to lawyers, in this case. I was surprised when writing the chapter on the A-12 Avenger II program in Strike from the Sea to discover that its termination was still in dispute. Given that it had occurred in January 1991, almost two decades before, that seemed unlikely until I realized that it involved a $2.3 billion claim by the Navy against GD and Boeing (which now owns McDonnell Douglas, GD's original partner in the ill-fated program). That sum consisted of a demand for the repayment of $1.3 billion in progress payments and $1 billion (and apparently still counting) in interest. Avoidance of the payment of that kind of money justifies the efforts of legions of lawyers.
There were eventually two trials. The contractors won the first in 1995, which the government successfully appealed, and the government won the second in 2001, which the contractors successfully appealed. (A 2002 settlement floundered because the contractors and the government couldn't agree on the value of the "in-kind payments", i.e. goods and services as opposed to cash, to be made by the contractors.) According to today's Wall Street Journal, the U.S. Court of Appeals for the Federal Circuit has finally ruled on the 2007 Claims Court ruling against the contractors, upholding it.
It's probably finally over but I wouldn't bet on it.