As a candidate in 2016, Sanders criticized Hillary Clinton over her family’s nonprofit, saying the foundation run by Clinton’s husband and daughter amounted to a back door for foreign leaders and others seeking to buy access and influence. 

…[The Sanders Institute] has accepted hundreds of thousands of dollars during its brief existence and has declined to disclose its donors.

….The lack of transparency and the family ties have drawn criticism from good-government advocates.

“For a politician who runs on fairness and socialist principles, this looks like the old political games,”

Think tank run by Bernie Sanders’ wife and son shuts down for now. Sanders Institute stops accepting donations and will close by end of May, as Bernie Sanders pursues presidential bid – CBS News