[3] Jenckes began his career at the Federal Reserve Bank of New York.
Afterwards he worked at McKinsey & Company in Washington, DC in the Media & Technology practice.
In 2001, he joined AOLas Senior Vice President, Messaging Communities and worked with the AIM and ICQ Brands and launched its advertising-financed consumer portal www.aol.com.
[2] Then he was the president of the Media and Content divisions of Grab Networks and before that he was the Chief Executive Officer for Voxant, Inc, a privately held new media company based in Reston, Virginia.
In 2017, Jenckes overtook Comcast’s ad-technology division as part of an operational restructuring that followed the company’s wave of acquisitions.