Meta Platforms faces scrutiny after a Reuters investigation found internal documents showing the company allowed large volumes of fraudulent and banned ads originating in China to run on Facebook, Instagram and WhatsApp while protecting ad revenue. Internal reviews and a Propellerfish consultancy found that roughly 19 percent of Meta’s China ad revenue last year — more than $3 billion of about $18.4 billion — came from scams, illegal gambling, pornography and other prohibited content, enforcement briefly cut that share to about 9 percent before the China-focused team was paused and the rate rose to about 16 percent by midyear.