Omnicom, one of the world’s largest advertising agencies, agreed to acquire rival Interpublic Group of Companies, Inc. in a deal that is expected to create the biggest ad agency in the world, with more than 100,000 employees and around US$25 billion in annual revenue.

Omnicom and Interpublic are US-based companies but both maintain significant operations in Canada, including major client portfolios and regional offices.

Latham & Watkins LLP is serving as legal counsel to Omnicom and PJT Partners is acting as financial advisor. Willkie Farr & Gallagher LLP is serving as legal counsel to Interpublic and Morgan Stanley is acting as financial advisor.

The deal is expected to close in the second half of 2025, subject to customary closing conditions and regulatory approvals.