3D Systems (DDD) and Stratasys (SSYS), which develop 3D printers, are advancing after research firm Piper Jaffray released upbeat notes on both stocks earlier today. After speaking with resellers and other industry contacts, Piper analyst Troy Jensen believes that 3D Systems and Stratasys will both report stronger than expected fourth quarter results. The 3D printing sector will grow for the next several years, according to the analyst. Jensen hiked his price target on 3D Systems to $73 from $55 and raised his target on Stratasys to $94 from $81. He maintained Overweight ratings on both stocks. In early afternoon trading, 3D Systems climbed $4.48, or 6.81%, to $70.30, while Stratasys added $1.69, or 1.89%, to $91.38.