SAN FRANCISCO — In creating the parent company Alphabet to better separate and structure its many businesses, Google Inc. cemented itself as the first Internet conglomerate.

In advising on the restructuring and implementation of Alphabet, Cleary Gottlieb Steen & Hamilton partner Ethan Klingsberg cemented himself as the conglomerate’s go-to corporate guy. New York-based Klingsberg first started representing the company on an ill-fated 2008 advertising deal with Yahoo Inc., where he advised on termination fees from the deal’s collapse. A year earlier, Google had paired Cleary’s antitrust lawyers with Wilson Sonsini Goodrich & Rosati for its $3.1 billion purchase of Doubleclick.