Earlier this week, Healthcare and pharmacy giant Walgreens Boots Alliance, which spent nearly $600 million on advertising in its fiscal year 2016, tapped WPP to provide a full suite of global advertising and marketing services after a review that began early last year, the companies confirmed.

When the deal was announced on Tuesday the companies weren’t talking about specific WPP shops that would be contributing to a new unit, Team WBA, to service the account.

Now it’s been disclosed that Grey and MediaCom will be key contributors to that dedicated unit.

Grey Group Chairman and CEO Jim Heekin issued a memo to staffers, obtained by MediaPost, confirming that the agency and several sibling shops had been named as key participants, including MediaCom.

In the memo, dated Feb. 2, Heekin wrote, “I am delighted to tell you that Grey has been named the lead advertising agency in the United States.  We will work with our valued WPP partners: MediaCom, Burson-Marsteller, and Townhouse.” Townhouse is a commercial production and distribution agency owned by WPP.

Heekin added, “Walgreens has been an iconic American brand for over a century.  Together with its Duane Reade unit, the company changed the shopping habits of our nation and became its most trusted pharmacy.  We are honored to add this premier company to our client roster in our Centennial year and help them continue to make marketing history.”