Megvii, a China-based facial recognition focused startup, files for a Hong Kong IPO; Megvii has raised $750M, reportedly at a $4B valuation, earlier this year (Arjun Kharpal/CNBC)

Arjun Kharpal / CNBC:
Megvii, a China-based facial recognition focused startup, files for a Hong Kong IPO; Megvii has raised $750M, reportedly at a $4B valuation, earlier this year  —  KEY POINTS  —  An attendee uses his smartphone to record a facial-recognition demonstration on himself at the Beijing Megvii Co. booth …