Today, in conjunction with the Creative Commons 5th Birthday celebration, Science Commons announces the Protocol for Implementing Open Access Data (“the Protocol”).The Protocol is a method for ensuring that scientific databases can be legally integrated with one another. The Protocol is built on the public domain status of data in many countries (including the United States) and provides legal certainty to both data deposit and data use. The protocol is not a license or legal tool in itself, but instead a methodology for a) creating such legal tools and b) marking data already in the public domain for machine-assisted discovery.