GTCR and Sycamore Partners private equity firms are taking CommerceHub Inc. (Nasdaq: CHUBA) private, acquiring the e-commerce services company for $1.1 billion.

The deal is expected to close in the third quarter of 2018, contingent on approvals of the CommerceHub (NASDAQ: CHUBA) shareholders and regulators. The all-cash deal proposed deal would pay CommerceHub shareholders premiums ranging from 25 percent to 30 percent, depending on their class of stock.

CommerceHub pitches itself as a “cloud-based commerce network” that allows retailers to better compete online with Amazon (Nasdaq: AMZN) and for brands to improve sales both online and through retailers. Its retail clients include Best Buy Co. (NYSE: BBY), JCPenney Co. (NYSE: JCP), Kmart and Sears Holdings Corp. (Nasdaq: SHLD), Toys ‘R’ Us, Walgreens Boots Alliance Inc. (Nasdaq: WBA) and Walmart Inc. (NYSE: WMT). Its brand client list includes Coleman, Dell (NYSE: DVMT), General Electrc Corp. (NYSE: GE), Konica Minolta, Mrs. Fields, Panasonic, Seiko, Serta and Whirlpool Corp. (NYSE: WHR).

CommerceHub is based in Albany, New York, with offices in Seattle and in Hertford, England. Executives at the PE firms plan to grow the company organically, according to their comments in announcing the deal. “We look forward to working with the CommerceHub team to help them grow by continuing to enable retailers’ and suppliers’ ecommerce offerings,” says Peter Morrow, Sycamore managing director.

Sycamore recently made a big bet on a retailer suffering from competition from Amazon. In September, New York PE firm completed its acquisition of Staples Inc. for about $6.9 billion, and the deal was among the largest retail acquisitions of the year. Sycamore also recently acquired NBG Home–designer and maker of affordable accent furniture, wall frames and lighting– from Kohlberg & Co.

GTCR, based in Chicago, was named Mergers & Acquisitions’ Private Equity Firm of the Year for 2013. Among its recent deals, GTCR acquired battery and power management system manufacturer EaglePicher Technologies from Apollo Global Management.