Diageo's purchase of Rosenblum Cellars was cleared by US antitrust officials this week.
The US Federal Trade Commission announced on Tuesday (February 13) the deal - thought to worth an estimated $105 million (53.5m) - was formally approved.
Rosenblum Cellars, which produces Zinfandel and Rhone varietal wines, is based in Alameda, California and was founded in 1978.