UPDATE 2-Dow Jones sells stake in Stoxx to Deutsche Boerse, SIX

* German/Swiss partners pay $301.9 mln for DJ's 1/3 stake

* DJ could get another 29 mln euros if performance good

* Equity-financed deal set to close in Q1 2010

* Future of DJ Indexes business in flux - WSJ

(Recasts, adds further details, background)

By Ajay Kamalakaran and Michael Shields

BANGALORE/FRANKFURT, Nov 12 (Reuters) - News Corp's (NWSA.O) Dow Jones & Co Inc is selling its stake in index provider Stoxx Ltd to Germany's Deutsche Boerse AG (DB1Gn.DE) and Swiss partner SIX Group for $309.1 million in cash, the companies said on Thursday.

The deal, a sign that Dow Jones may be looking to exit the index business, includes a payment of 132.1 million euros ($197.8 million) for Dow Jones's one-third stake in Stoxx and 74 million euros for intellectual property rights acquired by Stoxx, the German stock exchange operator said on Thursday.