Rubin's group, called Playground Global, has raised $48 million, according to a regulatory filing. It is structured as a venture capital fund, with no investors identified in the filing.
In addition to Rubin, Playground's board of directors includes co-founder (and ex-Microsoft exec) Peter Barrett, Rubin's former Google (and Danger) colleague Matt Hershenson and WebTV co-founder Bruce Leak.
UPDATE: The WSJ followed up with a story saying that investors in Playground Digital include Google, Hewlett-Packard (hpq) , Google, China's Hon Hai Precision Industry Co. and Redpoint Ventures (where Rubin also will serve as a venture partner).
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