Verizon are selling the platform to Automattic, just two years after acquiring the microblogging site.
The CEO of Automattic, Matt Mullenweg, has stated that Tumblr will continue to block pornographic content from the site after a ban was imposed last year after Apple removed it from the App Store.
He told Hacker News: "Adult content is not our forte either, and it creates a huge number of potential issues with app stores, payment providers, trust and safety.
"It's a problem area best suited for companies fully dedicated to creating a great experience there.
"I personally have very liberal views on these things, but supporting adult content as a business is very different."
In a blog post, he added: "I have worked on WordPress my entire adult life -- 16 years now -- and so the democratisation of publishing is near and dear to my heart.
"Tumblr and WordPress have always been very philosophically aligned there."
Verizon Media's CEO Guru Gowrappan called Automattic the "perfect partner" to take over and build on the legacy of the brand.
He said: "Today's announcement is the culmination of a thoughtful, thorough and strategic process.
"Tumblr is a marquee brand that has started movements, allowed for true identities to blossom and become home to many creative communities and fandoms.
"We are proud of what the team has accomplished and are happy to have found the perfect partner in Automattic."