Check out the companies making headlines after the bell:
Equifax shares rose more than 1 percent in extended trading. Earlier Thursday, the company announced
Spark Therapeutics's stock rose more than 5 percent after hours. An FDA advisory panel voted in favor of the company's gene therapy for a rare form of blindness.
Shares of Pacific Gas and Electric climbed more than 7 percent in extended trading before leveling out to nearly flat, after the stock closed down 6.7 percent during the regular session.