The move is part of OMG's strategy to deliver more measurable media options.
Singer's business cuts across brokerage and management for insert media, such as cooperative mailings and catalogue inserts, and internet cost-per-acquisition services.
Daryl Simm, OMG CEO, said: "Advertisers are increasingly focused on maximising return on investment and Singer Direct is a great fit with our strategy to provide innovative and more accountable media alternatives."
Fred Singer, founder and CEO of Singer Direct, said OMG's belief that insert media was still an "untapped advertising vehicle" contributed to the company's decision to sell to the bigger group.
Singer Direct will remain a standalone company, led by its existing management in Scarsdale, New York.
OMG is the media division of Omnicom Group. Its primary media businesses are OMD Worldwide and PHD Network, but it also includes specialist companies in areas such as search engine marketing, branded content production, asset barter, out-of-home media and discount newspapers.
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