An "open" playtest could be considered open to anyone who wishes to join, or it may refer to game designers recruiting testers from outside the design group. Prospective testers usually must complete a survey or provide their contact information in order to be considered for participation. A "closed" playtest is an internal testing process not available to the public. "Beta testing" normally refers to the final stages of testing just before going to market with a product, and is often run semi-open with a limited form of the game in order to find any last-minute problems. With all forms of playtesting it is not unusual for participants to be required to sign a non-disclosure agreement, in order to protect the game designer's copyrights.