The backers were not disclosed.
The company intends to use the capital to retire debt and fund continued product development and marketing.
Founded in 2009, SocialFlow has developed a technology platform that enables publishers to distribute engaging social content across Facebook, Twitter, Instagram, LinkedIn, Pinterest and Apple News. The company also provides publishers with monetization solutions that leverage their most effective content to improve advertising offerings and improve retention of paying subscribers.
The client roster includes half of the top 150 media companies including CNN, Condé Nast, Meredith, The Associated Press, and the BBC.