Uber is battling one of its own investors for Nokia’s map unit

Uber has a new rival in its efforts to buy Nokia’s $4 billion digital mapping business, and it’s an investment firm that just happens to hold Uber stock.

According to Reuters, Connecticut-based private equity firm General Atlantic is working on a bid for the Nokia business, called HERE, in partnership with German automakers Audi, BMW and Mercedes.

On the surface this development doesn’t look to surprising, since Uber has never identified General Atlantic as an investor, nor does General Atlantic publicly list Uber among its portfolio companies. In fact, the only real mention of General Atlantic and Uber in the same financing story came last May, when General Atlantic passed on buying into the ride-sharing giant because the valuation had gotten too rich.

Fortune has learned, however, that General Atlantic did recently become a small Uber shareholder. Sources familiar with the situation say that the private equity firm purchased Uber stock via a company-approved secondary at around a $30 billion valuation, most likely from some early venture capital backers that Uber allowed to partially cash out. Those same sources say that General Atlantic and Uber are aware of each other’s involvement in the Nokia process.

So if Uber loses out on HERE to the German automakers, it may have one of its own investors to thank. And if it wins, then General Atlantic still gets some exposure to HERE, albeit much less directly.

At the same time, an Uber win also would represent a victory for one of General Atlantic’s rival from the private equity space: Apax Partners. The Reuters report says that Apax is working with Uber on its bid, and that they also are joined by existing Uber shareholder Baidu (BIDU).

A third bid reportedly is coming from China’s Tencent, which is working with Swedish private equity firm EQT Partners.

General Atlantic declined to comment. Uber has not returned a request for comment.

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