Publicis, the world's fourth-largest advertising group which has vowed to fight for advertising spending despite the economic slump, unveiled a string of contracts on Friday.
Its MediaVest USA unit was named "Agency Of Reference" for Comcast Corporation's online and offline planning and buying duties.
The deal with Comcast, the largest US cable operator, is worth an estimated at roughly $500 million (Dh1.83 billion) per year, Publicis said. Other details were not available.
Separately, Starcom France won a four-year advertising deal with national health insurance agency CNAMTS. The budget is worth some $25.4m per year.
Finally, Mars Petcare UK named another Publicis unit, Zenith Optimedia, to handle its $21.4m media planning account, following a review. The business was until now handled by MediaCom, a unit of Britain's WPP.
Zenith Optimedia already handles the media buying for the United Kingdom's Mars.
Publicis Chief Executive Maurice Levy said earlier this month that the economic crisis made market visibility difficult but he was committed to winning market share this year and industry-best margins in 2009.
Earliler, Publicis had lost the $100m Hawlette Packard media account to Omnicom.
Omnicom won the computer manufacturer's media planning and buying duties, which were previously handled by Publicis Groupe's Zenith Optimedia.
HP called a review of its media account last November. Zenith Optimedia, which did re-pitch for the business, had held the account since 2004 and works with the company in 90 countries.