 CHICAGO--BUSINESS WIRE--Oak Street Health, Inc. Oak Street NYSE: OSH, a network of value-based, primary care centers for adults on Medicare, today announced the commencement of an underwritten public offering of 9,000,000 shares of its common stock by certain selling stockholders. Such selling stockholders also intend to grant the underwriters a 30-day option to purchase up to an additional 1,350,000 shares of Oak Streets common stock. Oak Street will not receive any of the proceeds fr 