Chilean firm Adimark provides custom research in the retail, financial services and telecommunications sectors.
Founded in 1974, Adimark clients include the Chilean government, the national wi-fi company Entel, and Chile's biggest beer and third-largest soft drinks manufacturer, CCU. Last year, the company, which has 151 staff, has sales of €5.1m (£3.5m).
Toronto-based firm Research Dynamics provides custom research to companies in the FMCG, financial services and ICT markets.
Major clients include Imperial Tobacco, the Canadian subsidiary of British American Tobacco, the Bank of Montreal and Microsoft. Last year, the company generated €3.4m worth of sales.
Petra Heinlein, GfK management board member, said: "Following the acquisition of NOP World, which has significantly strengthened our positioning in the US, this most recent majority takeover of Research Dynamics and Adimark enables us to consolidate our business activities in two other key markets in America."
Separately, GfK has increased its shareholding in German geomarketing company, GfK Macon AG, from 51% to 100%.
The company, which was established in 1991 and acquired by GfK in 2002, provides software such as RegioGraph and District as well as digital maps acoss the world.
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