The deal, set up by private equity firm Carlyle, makes it the largest independent search marketing company, with over 300 customers, including Hilton, British Airways, AOL and Barclays.
Bigmouth owners Stephen and Heather Leach cashed in from the deal but have reinvested a significant part buying equity in the combined group. The Bigmouth brand will be retained alongside the Global Media brand.
Global Media has offices in London and Manchester in the UK, and Munich, Paris, Milan, Oslo, Stockholm and Moscow in Europe and Seoul in Asia. Bigmouth is based in London, Edinburgh and New York.
Thomas Gerteis, previously CEO of Global Media, will be CEO of the combined group and Steven Leach, previously CEO of Bigmouth, will be in charge of all UK and US operations. His role will be chief strategy officer and he will have responsibility for both brands.
Leach said: "We're delighted to be partnering with Global Media. It's no secret that we have had a number of approaches for a deal but it wasn't just about the investment for us, we needed to find a partner with shared chemistry and vision for growth. In Global Media we've found that. It's very exciting to be at the cutting edge of this industry, and also filing the gap to be the world's first fully integrated search provider."
Search marketing has expanded rapidly and now accounts for more than half of all internet advertising in the UK. Bigmouth Media specialises in assisting brands to buy and plan their advertising campaigns on internet search engines, such as bidding for keywords during search.
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