San Diego-based Bumble Bee Seafoods LLC, one of the world’s largest seafood purveyors, said it agreed to be acquired by Thai Union Frozen Products Public Company Ltd. for $1.51 billion.

The deal will allow Thai Union, which owns Chicken of the Sea and the world’s largest processor of tuna, to improve its operating efficiencies in sourcing and production, as well as new product development, the company said.

“This deal is the largest acquisition in the history of our company and one of the most exciting external growth propositions,” said Thiraphong Chansiri, president and CEO of Thai Union.

Bumble Bee is privately owned by the Pan-Atlantic private equity firm, Lion Capital.

The parties said while a definitive closing date cannot be determined, they expect the transaction to close in the second half of 2015.

The transaction is subject to clearance by U.S. antitrust authorities and other closing conditions in the sale agreement.

Bumble Bee, which was founded in 1899, generated annual sales of about $1 billion and an estimated earnings before income taxes and depreciation and amortization of $145 million this year, the companies said.

Post synergies, the transaction is valued at 8.6 times Bumble Bee’s EBIDA for this year, the companies said.

Bumble Bee moved its administrative headquarters and its 140 local employees this year to the Showley Bros. Candy Factory building in the East Village.