GBU-53 Small Diameter Bomb
A second generation beyond the GBU-39 Small Diameter Bomb, the U.S. GBU-53 Small Diameter Bomb also is optimized to minimize collateral damage, but adds multiple guidance modes and the ability to hit moving targets. Not only is it unpowered, but it is also a glide bomb, with folding wings that allow it to hit targets beyond the range permitted by gravity and initial momentum.
While the weapon is intended to be used by all military services, the U.S. Air Force is managing selection and procurement. During the prototype development, one of the challenges was shortening the weapon length so eight, rather than six, could fit into the bomb bay of the F-35B Lightning II aircraft of the U.S. Marine Corps.
Raytheon is the prime contractor, teaming with Lockheed Martin. Boeing beat Raytheon in competition for the GBU-39. Raytheon, however, is teaming with Lockheed Martin for the Joint Air-Ground Missile (JAGM) project, for which it developed the triple-mode guidance used in the GBU-53. In the JAGM project, Raytheon teams with Boeing against Lockheed Martin.
The GBU-53 is in development. It still has GPS guidance, but adds triple-mode (laser, imaging infrared and radar) guidance developed for the JAGM.  As opposed to the GBU-39, the GBU-39 can communicate, using the Joint Tactical Information Distribution System, to aircraft — one aircraft can launch it and another aircraft can control it.
- "Moving Target: Raytheon’s GBU-53 Small Diameter Bomb II", Defense Industry Daily, 21 November 2010