"Another ad that Facebook is targeting is the one that promises the absence of risk. That seems to have been the approach of Bitconnect, which was guaranteeing fixed returns and has since been hit with its second class action lawsuit claiming an investment scam."

Bitconnects action leads other cryptos to fall...

Source: https://www.ccn.com/facebook-takes-aim-at-icos-cryptocurrencies-in-new-ad-guidelines/