Provided is a safety joint with a moveable seal designed to prevent hydrostatic locking. The safety joint is primarily made up assembling a pin end having a first seal, a threaded connection, and a second, moveable seal to a box end. The moveable seal is disposed in a recess formed in the pin end and includes an O-ring and a spring. When the safety joint is assembled downhole, a volume of fluid may become trapped between the first seal and the second seal. The trapped fluid in turn pushes the O-ring towards the spring, thereby limiting pressure build-up by substantially maintaining the volume trapped between the first and second seals.