The Greenport Basin and Construction Company, known by various names throughout its history, but most recently named the Greenport Yacht & Shipbuilding Company, is a shipbuilder in Greenport, Suffolk County, New York. It was established in the 19th century by brothers Pliny C. Brigham and Theodore W. Brigham.^[1][2] One local history relates:

Greenport prospered due to the menhaden industry; 64 boats were in service and seven under construction in 1879. By this time, shipbuilding (pleasure craft, cargo vessels, fishing vessels) boomed in Greenport. The Greenport Basin and Construction Company, famous yacht builders, became a large repair and docking facility for menhaden vessels. (Today, the company is known as Greenport Yacht and Shipbuilding.) Menhaden vessels or "bunker boats" were said to have lined the shoreline along Main and Front Streets.^[3]

The company built dozens of ships for the United States Navy during World War I and World War II, as well as building yachts for private customers.^[2] In 1917 the company became involved in a tax case against the United States, in which it protested the assessment of an "excess profits" tax.^[1] The case made its way to the U.S. Supreme Court, where the company finally lost the decision in 1923.^[1][4] In 1970, the company was acquired by Stephen Clarke, and thereafter turned its attention from ship construction to ship maintenance and repairs, and historic preservation of ships.^[1]