This question already has an answer here:
The ACM license states
(iii) Post the Accepted Version of the Work on (1) the Author’s home
page, (2) the Owner’s institutional repository, (3) any repository
legally mandated by an agency funding the research on which the Work
is based, and (4) any non-commercial repository or aggregation that
does not duplicate ACM tables of contents, i.e., whose patterns of
links do not substantially duplicate an ACM-copyrighted volume or
issue. Non-commercial repositories are here understood as repositories
owned by non-profit organizations that do not charge a fee for
accessing deposited articles and that do not sell advertising or
otherwise profit from serving articles.
Does this (somehow) include ResearchGate?