London-Based S4 Capital in Early Merger Talks With MSQ Partners; Shares Rise 14% Amid £130 Million Market Cap

Martin Sorrell's advertising group, S4 Capital, is in early-stage talks to merge with MSQ Partners, a private equity-owned marketing agency. The discussions were confirmed by S4 Capital in a statement to the stock market on August 11, 2025, following initial reports over the weekend. S4 Capital, which is based in London and currently has a market capitalization of approximately £130 million, has seen its stock decline about 35% in 2025. News of the potential merger caused S4 Capital's shares to rise by as much as 14%. The talks represent a potential combination of two marketing-focused entities, with MSQ Partners known as the owner of Monks, another agency. The negotiations are ongoing and at an early stage.