Two companies sued each other over rights and technology used in an effort to recover "hundreds of pounds of gold" lost in a 1901 shipwreck.
The SS Islander sank near Juneau, Alaska in 1901, killing 40 passengers, according to the two federal complaints.
The ship was believed to be transporting "hundreds of pounds of gold" from the Klondike to Seattle and San Francisco.
Salvagers say that if there were gold on board, it would likely be "single gold bars and boxes of gold bars" buried under as much as 8 feet of silt.
MK Salvage Venture LLC, of Seattle, sued Tetra Tech EC, a New Jersey corporation with offices in Seattle, in one complaint.
Tetra Tech returned the favor in its complaint against MK Salvage. MK Salvage Venture, preparing to recover artifacts and treasure from the Islander, hired Tetra Tech to do technical work for the operation.
Tetra Tech claims MK Salvage refused to pay it $630,200 for data analysis and survey work.
Tetra Tech sued for breach of contract, claiming it "fully completed the scope of work and otherwise fully performed all services." Tetra Tech claims it also is entitled to $175,000 if it documents and recovers at least 137 pounds of gold.