https://www.siliconvalley.com/2019/12/20/californians-can-now-check-legal-pot-dealers-using-qr-codes/

SACRAMENTO — California marijuana users can now turn to their smartphones to find out if a dispensary is legit.

The Bureau of Cannabis Control on Thursday announced a program encouraging licensed cannabis retailers to post QR codes in their store windows. The checkerboard codes can be scanned by a cellphone camera linking the reader to the bureau’s online license bureau.