FORTUNE — Big move in the East Coast venture capital world, as Nick Beim has left Matrix Partners for Venrock.

Beim had spent the past 12 years with Matrix, where he led investments in such technology companies as Gilt Groupe, and Exited deals included OatSystems (acquired by Check Point Systems) and JBoss (acquired by RedHat).

Beim will serve as a New York-based managing director with Venrock, continuing to focus on the Internet, mobile, SaaS, adtech and big data sectors.

Beim and a Venrock spokeswoman both declined to comment.

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