The Einhorn effect appears to be alive and well.
Shares of SunEdison and Conn's jumped Tuesday on news that David Einhorn's Greenlight Capital had opened new positions in them, continuing the tradition of traders acting in agreement with the hedge fund manager.
SunEdison rose from $18.79 a share just before news broke to close at just above $20, up 11.8 percent for the day. Conn's was trading at $43.82 until shortly before 2 p.m.; that shot up to about $48 before settling at $46.98 at market close, up 7.65 percent on the day. Sun rose marginally in Wednesday trading, while Conn's gave back some of its gains.
Those moves echoed the sharp movements Einhorn has caused in the past. In May 2012, for example, shares of Herbalife fell about 20 percent after Einhorn asked questions during a company call. In December 2010, Einhorn said on CNBC that he had bought a stake in Sprint Nextel; shares jumped more than 6 percent that day.