Silver Lake Partners, the private equity firm working with Michael Dell, has disclosed in a regulatory filing that some of its limited partners are making an aggregate co-investment of $350 million. In other words, some institutions that already have exposure to Dell (DELL) via their existing commitments to Silver Lake are effectively doubling down (or more) on this particular deal.

Silver Lake originally agreed to invest just over $1.4 billion into Dell our of its $1.03 billion fourth fund, so this means the fund itself only will have around $1.05 billion of exposure. That’s an important number, since private equity funds try not to let any one investment account for more than 10% of their total capital.

A source familiar with the situation says that LP co-invest interest was “heavy” and “oversubscribed.”

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