SunEdison Inc (NYSE:SUNE) was up more than 9% in trading today (currently +7.9%) after Greenlight Capital’s David Einhorn talked it up during a talk at today’s Robin Hood Investor’s Conference, reports Julia La Roche at Business Insider, but considering this was already one of David Einhorn’s largest positions his comments shouldn’t have surprised anyone.

David Einhorn was adding SUNE at a higher price earlier this year

SunEdison Inc (NYSE:SUNE) may be the best performing solar stock of the year, but in this case looking at the aggregate return hides important details. At the end of June, Greenlight Capital owned 21 million shares of SUNE worth $481 million and making up 6.7% of the fund’s portfolio, a 79% quarter-on-quarter increase. At the time, SUNE was trading for $23, close to its 52-week high.

Greenlight's David Einhorn Still Long SUNE, Hedges On Europe

So if David Einhorn was willing to significantly add to his position while SunEdison Inc (NYSE:SUNE) was trading in the high teens and lows 20s, either something significant would have to change in his valuation, or he would view prices in the mid-teens as a bargain. As he made clear today, it’s the former, and the next time Greenlight Capital files a 13F we can expect to see its position on SUNE to have grown even larger – by share count if not market value.

It’s possible that David Einhorn has also presented new analysis or a new angle on the SunEdison Inc (NYSE:SUNE) long, but considering how quickly the markets responded to a presentation that was closed to the press, it seems more likely that his reassurance was enough to calm nervous investors.

David Einhorn is long Greek banks, short French debt

While Greece seems to be the weakest economy in Europe, David Einhorn also said that he owns warrants for Greek banks Alpha Bank A.E. (ADR) (OTCMKTS:ALBKY) and Piraeus Bank SA (OTCMKTS:BPIRY), apparently betting that they are as undervalued now as they’re ever going to be, but has gone short on French debt. The French government has recently refused to make further changes to its annual budget to keep its deficit within EU limits, creating a controversy that hasn’t fully played out.

Since both French debt and Greek banks rely on the ECB for support, if not entirely in the same way, shorting one while going long on the other could also give Greenlight some protection if the ECB moves in an unexpected direction with either far more or less accommodative monetary policy than markets are currently expecting, giving him a kind of macro hedge.