Abstract: An improved picture frame clamp assembly includes an L-shaped screw plate, and an L-shaped backing plate. Both plates are elastically secured to each other by an elastic member, resulting in an L-shaped clamp assembly with the screw plate shifted slightly with respect to the backing plate. The screw plate and the backing plate each include two legs. Each of these legs are sized to fit within a receiving channel of a picture frame section. The magnitude of offset between the screw plate and the backing plate is preferably such that the sum of this offset distance and the width of the legs is equal to or larger than the width of the receiving channel. This arrangement ensures that upon insertion into the receiving channel of a frame section, the screw plate will be biased against an inside wall of the receiving channel, while the backing plate will be biased against an opposing wall of the receiving channel due to the spring bias of the elastic member.