DV-9999
When DV-9999 was discovered drifting in Jupiter’s orbit by an extremely classified American military black-ops program, it was the US Navy that ended up getting the derelict interstellar ship after it was towed back to Earth (it is, again, an extremely classified program). Oh, sure, other groups tried to claim it, but the Navy just had the better bureaucratic knife-fighters this time. Sometimes it just comes down to that. It probably also helped that the discovers’ were sort of related to the Navy, in a fairly recondite sort of way. Besides, the Navy was willing enough to share.
Of course, the value of DV-9999 is actually a somewhat complicated question. Its tonnage is about 200 tons, and looks like it was designed for 6 crew members and 4 passengers (assuming human-sizes throughout). There are extensive open spaces inside the ship itself, with direct access to space via a set of doors. The outside also has two hardpoints that look like they were designed to fit weapons pods of some sort; one of the hardpoints is occupied with broken machinery, and one is a melted pile of slag. DV-9999 is also heavily damaged and open to vacuum, with burn-throughs and impact craters consistent with energy and explosive weapons.