Tumblr founder David Karp is resigning

Rob Kim/Getty Images for Tumbl

David Karp.

Tumblr founder David Karp is resigning from the company he created 10 years ago, he announced in a memo sent to employees on Monday.

Karp said he would step down at the end of the year after "months of reflection on my personal ambitions," according to the memo, which Karp also published on his personal Tumblr blog.

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Tumblr COO Jeff D'Onofrio will take over Karp's responsibilities as the leader and public face of the Oath-owned subsidiary, according to an Oath spokesperson.

"David founded Tumblr ten years ago as a space for the world's creators, and we thank him for his commitment and passion driving the growth of the platform to almost 380 million blogs and over 155 billion posts," the spokesperson told Business Insider.

This story is developing. Check back for updates.

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