Science is the systematic enterprise of gathering knowledge about the universe and organizing and condensing that knowledge into testable laws and theories.
The success and credibility of science are anchored in the willingness of scientists to:
1. Expose their ideas and results to independent testing and replication by others. This requires the open exchange of data, procedures and materials.
2. Abandon or modify previously accepted conclusions when confronted with more complete or reliable experimental or observational evidence.
Adherence to these principles provides a mechanism for self-correction that is the foundation of the credibility of science.
I assume that the APS deems "open exchange" to include more than just sharing data and methods with like-minded scientists while withholding it from skeptical ones.