Horizon Lines Inc., a U.S.-flagged ocean carrier whose founder invented the concept of shipping goods in containers, is winding down its operations after agreeing to sell the bulk of its business to Matson Inc. and The Pasha Group for nearly $600 million.

Ocean shipper Horizon Lines earned a profit of $3.7 million, or 12 cents a share, in the second quarter, compared with a loss of $31.1 million, or $1.02, a year earlier.