The merger follows the acquisition of Swetenhams by Swedish media group Bonnier, which is behind many international editions of Metro-branded newspapers.
Prospect Swetenhams will offer both UK and international list broking and list management in the business-to-consumer and business-to-business markets. The company also said it was investing heavily in owned B2B data and has an extensive range of data processing services.
Hugh Bessant, managing director of Prospect Swetenhams, said: "Prospect Swetenhams offers the UK's largest team of data experts and an unparalleled depth and breadth of expertise underpinned by leading-edge technology. Quite simply, Prospect Swetenhams is the market leader in size, expertise, technology and client service."
Simon Swetenham, who is focused on the integration of the businesses in a consultancy role at Prospect Swetenhams, said: "In terms of ensuring a seamless transition it will be business as usual, but Prospect Swetenhams offers an even stronger proposition for existing and new clients. The launch of Prospect Swetenhams means that we can offer the level of personal care you can expect with a smaller company backed by the resources you can only find in a larger organisation."
The Prospect Shop started as a business in 1999. Initially a joint venture, The Prospect Shop has developed the Prospect B2B database alongside a growing list management.
Swetenhams, established in 1991, launched as a provider of list broking, list management and data management services in the UK.
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