Shares of Omnicom Group (OMC) plummeted 5.05% in intraday trading on Wednesday after the advertising giant reported disappointing first-quarter results and lowered its full-year organic growth guidance. The company's cautious outlook, citing uncertainties around client spending amid potential tariffs, sent shockwaves through the advertising industry.

Omnicom's Q1 revenue missed analysts' expectations, with organic growth of 3.4% falling short of estimates. More concerning for investors was the company's decision to lower the bottom end of its 2025 organic growth guidance to 2.5% from the previous 3%, while maintaining the upper end at 4.5%. This adjustment reflects growing uncertainties in the advertising market, particularly around potential impacts from tariffs on client spending.

The cautious outlook from Omnicom has had a ripple effect across the advertising sector. Shares of rival agencies, including Publicis, WPP, and Havas, also traded lower in Europe following the news. Analysts have responded by lowering their price targets for Omnicom, with Wells Fargo cutting its target to $84 from $99, and MoffettNathanson reducing its target to $85 from $92. The advertising industry now faces increased scrutiny as investors await further clarity on how potential tariffs and economic uncertainties may impact marketing budgets in the coming quarters.