Lockheed Martin has completed its acquisition of Ultra Maritime, bringing a sonar and anti-submarine warfare (ASW) specialist with a large Nova Scotia operation into the company.

The deal, announced in July at US$3.45 billion, places Ultra Maritime inside Lockheed Martin’s Rotary and Mission Systems business. Private equity firm Advent International sold the company, which it held as part of Cobham Ultra.

Ultra Maritime builds sonobuoys, towed and hull-mounted sonar arrays, torpedo defence systems, radar and autonomous maritime sensors for allied navies.

Ultra Maritime employs about 400 people in Dartmouth, N.S. Lockheed Martin says that business will add to Lockheed Martin Canada’s workforce.

The Dartmouth site designs and builds towed acoustic arrays that give warships active and passive sonar to identify torpedo threats and support wider underwater surveillance. It also produces G-size sonobuoys, miniaturized buoys that detect and locate submarines and uncrewed underwater vehicles. Lockheed Martin describes them as the only products of their kind available worldwide.

Kristen Leroux, Lockheed Martin’s vice-president and regional executive for Canada and Latin America, called the Canadian operation a towed array centre of excellence whose globally deployed arrays are developed and built entirely in Canada.

“Much like Lockheed Martin Canada, and our Canadian-built CMS 330 combat management system, this stems from a longstanding legacy of Canadian engineering and manufacturing excellence,” she said. “By bringing together our complementary strengths, we will expand delivery of Canadian sovereign solutions, deepen Canadian expertise, and build resilience across our defence supply chain.”

Lockheed Martin says Ultra Maritime’s international reach and ASW product lines, including sonobuoys, towed arrays and hull-mounted sonar, will expand its ability to offer sonar across next-generation naval platforms.

“Securing the undersea domain starts with giving sailors the tools and confidence to find, track and deter threats that put ships and crews at risk,” said Stephanie Hill, president of Rotary and Mission Systems at Lockheed Martin.

Hill framed the deal as a long-term commitment to combine the two companies’ technology and people “to meet our partners’ urgent and growing demand for undersea warfare capability worldwide.”

Ultra Maritime also brings work in autonomy. In 2025, it partnered with Anduril Industries on autonomous ocean sensing and with General Atomics Aeronautical Systems on uncrewed airborne ASW. Earlier this year, it won a U.S. Navy development contract for an underwater acoustic decoy designed to protect ships and submarines from torpedoes.

The two companies already work together in Canada. Lockheed Martin Canada, the combat systems integrator for the River-class destroyer program, awarded Ultra Maritime an $89-million contract in March 2025 for three shipsets of surface ship torpedo defence systems, with the work based in Dartmouth.

That supplier relationship now moves in-house. Lockheed Martin Canada’s CMS 330 runs on the Halifax-class frigates and forms part of the River-class combat system. The company now owns both the combat management software and a key undersea sensor supplier on the navy’s next major surface combatant.

Undersea surveillance has moved up the Royal Canadian Navy’s priority list as Ottawa pursues new submarines under the Canadian Patrol Submarine Project and better underwater domain awareness, including in the Arctic. Sensors designed and built in Dartmouth give Lockheed Martin Canada a domestic undersea product line to offer as those programs take shape.

The deal also fits the direction of Canada’s Defence Industrial Strategy, which favours sovereign capability and domestic production. Leroux pointed to that directly, promising to “expand delivery of Canadian sovereign solutions.”

Lockheed Martin did not say whether it plans to expand the Dartmouth operation, change its product lines or rebrand the business. It also did not say how Ultra Maritime will fit within Lockheed Martin Canada’s existing structure.