Michael Larson to lead Diversified Agency Services & Omnicom Health in merged Omnicom-IPG

Omnicom’s post-Interpublic acquisition leadership structure continues to take shape, and at the centre of a critical operational pillar stands Michael Larson, who has been appointed CEO of Diversified Agency Services (DAS) and Omnicom Health. This role places him in a pivotal governance position over Omnicom’s network of specialized agencies spanning healthcare, medical communications, brand consulting and performance-led marketing services. His oversight aligns directly with the strategic intent of the merger, which Omnicom framed as uniting the industry’s most comprehensive portfolio of connected capabilities, powered by Omni, its intelligence and data-driven platform.

The company has emphasized that these capabilities, blended with exceptional leadership talent, deliver competitive advantage across every dimension of modern marketing and sales. In this context, Larson’s portfolio sits at the operational core of the capabilities strategy, ensuring specialization scales effectively and cohesively within the merged enterprise.

Under Larson’s unified division sit several executive leaders overseeing major verticals. One of the key reportees is Dana Maiman, CEO of Omnicom Health, who brings deep sectoral expertise in healthcare, spanning professional and consumer-facing communications, patient engagement and health-related marketing services.

Dana’s leadership role is noted for her intellectual horsepower and long-term navigation of healthcare communications ecosystems, as well as her ability to shepherd complex networks of health agencies with credibility and authority. Her oversight covers areas such as medical communications, integrated omni-channel healthcare brand campaigns and engagement models that connect the medical professional audience, patient communities and healthcare organizations. Dana’s experience within this specialized environment positions her as a subject-matter steward for Omnicom’s most regulated, precision-governed marketing category, one which is highly influenced by compliance, ethics and scientific communication standards.

Another leader within Larson’s reporting structure is Mark O’Brien, CEO of Omnicom Branding, who oversees the group’s globally recognized brand consultancies including Interbrand, Siegel+Gale, Sterling Brands and Wolff Olins. These agencies operate across areas such as brand valuation, corporate identity, naming, positioning, design and brand architecture, the intellectual blueprinting of corporate and consumer-facing image systems.

O’Brien’s oversight of these networks suggests that Omnicom, in the merged environment, is retaining the core value of strategic branding, not merely as a creative discipline but as a commercial guidance function for clients navigating market differentiation and category-led positioning challenges. With brands increasingly operating in omnichannel, multimarket, multi-stakeholder environments, this portfolio under O’Brien functions as Omnicom’s brand-engineering layer, shaping perception before marketing execution takes over further downstream.

Completing the trio of direct reportees is Luke Taylor, CEO of Omnicom Precision Marketing, responsible for Creador, Critical Mass and RAPP. Luke’s leadership sits at the operational leading edge of personalization, data-fueled consumer targeting and digital experience optimization. His function addresses modern marketing’s strongest demands, precision deployment, consumer journeys, segmentation intelligence and the measurable performance layer of communications.

While O’Brien’s portfolio shapes what a brand is and Maiman shapes how a health message lands, Taylor’s remit determines who sees what, how often and where. Under the merged Omnicom-IPG umbrella, precision marketing is expected to integrate closely with Omni intelligence, reinforcing the organization’s ambition to deliver progressively smarter, data-responsive campaigns.

The inclusion of Michael Larson at the head of DAS and Omnicom Health reflects a larger structural thinking in the merged organization. As Omnicom stated in its merger announcement, the new entity unites the industry’s most comprehensive and connected portfolio of capabilities, powered by Omni, addressing clients’ critical growth priorities and offering competitive edge across modern marketing and sales.

Additionally, the leadership structure includes enterprise-wide systems such as Client Success Leadership and a Global Growth Team to accelerate commercial integration beginning February 2025. Larson’s division is expected to be one of the key beneficiaries and contributors to these enterprise initiatives, given the depth, specialization and scalability of the entities under his management.

In sum, Michael Larson represents a cornerstone of the merged company’s operational and strategic DNA. His leadership, combined with Dana Maiman’s stewardship of health communications, Mark O’Brien’s command of strategic branding and Luke Taylor’s executional command of precision marketing, creates a tightly aligned chain of specialization. Together, they exemplify the deeper strategic thesis of the merger: combining specialized agency expertise with connected intelligence and unified leadership to deliver impact at client scale.