Hamid R. Jamali has self-archived "Copyright Compliance and Infringement in ResearchGate Full-Text Journal Articles."
Here's an excerpt:
This study aims to investigate the extent to which ResearchGate members as authors of journal articles comply with publishers' copyright policies when they self-archive full-text of their articles on ResearchGate. . . . The key finding was that 201 (51.3%) out of 392 non-OA articles infringed the copyright and were non-compliant with publishers' policy. While 88.3% of journals allowed some form of self-archiving (SHERPA/RoMEO green, blue or yellow journals), the majority of non-compliant cases (97.5%) occurred when authors self-archived publishers' PDF files (final published version).