— Pattern Energy Group Inc. — Wind power company, based in San Francisco, with eight projects in U.S., Canada and Chile. Expected to offer 16 million shares, priced $19 to $21.
— Premier Inc. — A company that collects and analyzes clinical and financial data for health care facilities, based in Charlotte, N.C. Expected to offer 28.2 million shares, priced $23 to $26.
— RingCentral Inc. — Cloud-based phone system provider for small businesses, based in San Mateo, Calif. Expected to offer 7.5 million shares, priced $11 to $13.
— Tecogen Inc. — A maker of natural gas-fueled heat and power products that aim to reduce energy costs and greenhouse gas emissions, based in Waltham, Mass. Expected to offer 3 million shares, priced $6 to $8.