Option traders are looking for more gains in Yingli Green Energy, which spiked higher at the end of last week.
OptionMonster's tracking systems detected heavy buying in the Chinese solar-technology company's August 4 calls, where 5,558 contracts traded for $0.25 to $0.45 on Friday. The volume was nine times higher than the strike's open interest of just 599 calls before the session began, indicating that this is fresh buying.
Yingli surged 13.25 percent to close the session at $3.76. The beaten-down solar sector has cooled in the last month after a big run earlier this year, but Yingli had been trading toward the upper end of its recent range leading up to Friday's jump.