What can be done about ResearchGate?

What is the deal with researchgate? Does anyone use it? They keep sending me spam emails with the name of colleagues (and today my boss) in the "From" field. How can they get away with this?

Is there anywhere to complain about this? In the UK we have the Information Commisioners Office where you can report companies, but I guess RG are not based in the UK. Is there anything similar in the US? Are there any representatives from researchgate on reddit who could explain this practice?

I'm going to join Academia.edu just because I hate researchgate so much...