Omnicom Group is in advanced talks to acquire Interpublic Group in an all-stock, stock-for-stock transaction where Interpublic shareholders will receive 0.344 Omnicom shares per Interpublic share. The merger, expected to be announced as soon as this week, would create the world's largest advertising company with combined annual revenues exceeding $25 billion. Omnicom shareholders will own approximately 60.6% of the combined company, which will retain the Omnicom name. The deal is anticipated to generate expected synergies of $750 million and is set to close in the second half of 2025, subject to regulatory approvals. Omnicom CEO John Wren and IPG CEO Philippe Krakowsky will lead the new entity.