The Middleby Corp. said net sales for the third quarter of 2015 increased 11.1 percent on strong performance of its commercial food service division. The manufacturer of equipment for the commercial food service, food processing and residential kitchen industries also said recent acquisitions helped boost the quarter's result, Net sales in its Commercial Foodservice Equipment Group increased $28.1 million to $290.9 million in the quarter, compared to $262.8 million the same period in 2014.