PORTLAND, Maine — Was the wooden fishing vessel Sirius seaworthy when it sank four years ago, 60 miles off the coast of Rockland?

Port Clyde fisherman Gary Thorbjornson perished when the boat sank, and his widow and the two surviving crew members — including Thorbjornson’s son — sued the owner of the boat for alleged negligence and unseaworthiness.

At least $400,000 in damages hung in the balance.

On Friday, a federal jury in Portland ruled after a three-day trial that the boat was shipshape when it went down, finding in favor of the owners of the Sirius.

“Plaintiffs have no evidence to prove negligence,” wrote attorney Michael X. Savasuk of Portland in an Aug. 26 pretrial brief. “To date, no one knows the actual cause of the sinking.”

Savasuk represented the corporation that owned the Sirius. Principals of the family-owned corporation included Gary Thorbjornson, his father, Ed Thorbjornson, and his uncle Travis Thorbjornson.

Savasuk wrote that the vessel’s owners had taken pains to keep the Sirius, which was built in 1958, in good repair — including a $90,000 rebuild at the Lyman Morse Boatyard in Thomaston a decade before the sinking. They also had hauled the Sirius in June 2005 to sand the hull, recaulk and paint, the attorney wrote.

“The actions taken by Defendant ... in preparing the vessel to be staunch and seaworthy, were more than prudent and reasonable under the circumstances,” wrote the attorney.

The Sirius had been loaded with 10,000 pounds of groundfish around dusk on July 13, 2005, and was preparing to head home when the “leaky vessel’s pumps just couldn’t keep up,” a family member told the Bangor Daily News at that time. Crew members hailed the fishing vessel Irene & Alton by cell phone, and reported they were abandoning ship. The captain, 42-year-old Gary Thorbjornson, was heading below deck to fetch survival suits when the boat rolled into the sea, toppling all three men overboard.

Garrett Thorbjornson, the captain’s 17-year-old son, and crewman David Wilgus, 19, found the life raft and shared one survival suit. They fired several flares into the sky, and within an hour were rescued by the Irene & Alton, according to the BDN report.

The Sirius was one of four draggers in Eddie Thorbjornson’s fleet, which also included a fiberglass boat, a steel boat and another wooden boat. After the boat sank, family members told the BDN that the Sirius was well-kept, but it was 50 years old and used as kind of a spare boat.

“At the time the vessel sank, the seas were no less than 3-5 feet and no greater than 5-7 feet. The wind was minimal, which was well within normal and expected weather conditions for a groundfishing trawler fishing out of Port Clyde such as the F/V Sirius,” wrote David F. Anderson of Boston, attorney for the plaintiffs, in his trial brief of Aug. 26.

The attorney detailed the Sirius’ second-to-last trip of early July 2005, alleging that “something struck the underside of the vessel” as the crew hauled in the fishing gear. Both Gary and Garrett Thorbjornson believed that the gear struck the underside of the Sirius, Anderson wrote.

“Capt. Gary Thorbjornson notified Garrett Thorbjornson that the vessel was taking on water and said, “we’re sinking,” Anderson wrote.

Seawater was flooding the boat’s fish hold, but Garrett Thorbjornson started bailing and the Sirius made it back to port, according to the brief. The boat wasn’t repaired after that trip, although a diver checked it below the waterline, Anderson wrote.

Garrett Thorbjornson and Wilgus filed a civil suit in the Maine District of the U.S. District Court against the F/V Sirius Inc. for personal injuries under the Jones Act and the general maritime law of unseaworthiness. Gary Thorbjornson’s widow, Tammy Thorbjornson, brought a civil suit against the corporation on behalf of her husband and on behalf of herself under the general maritime law and the Jones Act. The two cases were consolidated against the Sirius last July.

Tammy Thorbjornson claimed damages for “loss of support on behalf of herself as wife” for $625,000, plus a loss of $125,000 for Gary Thorbjornson’s household services. She also claimed a total of $200,000 on behalf of Garrett Thorbjornson and Erica Thorbjornson, according to the plaintiffs’ trial brief.

Efforts Monday to reach any of the parties in the lawsuit were unsuccessful.