JMP Securities analyst Joseph Osha downgraded First Solar (FSLR) two notches, to Underperform from Outperform, as he believes that recent policy developments in China that have "shaken global markets" will likely to put pressure on margins past 2019.

Pricing pressure is likely to accelerate outside of the U.S., and even in the U.S. pricing may decline as Chinese suppliers look to compensate for a sharp decline in expected demand at home, Osha tells investors.

He lowered his price target on First Solar shares to $46 from $87.