Furthermore the logo should be etched onto the lens.
Do all raybans have rb etching. Try checking for the logos instead. If the etching is missing, or a low quality or painted on the glasses will be fake. If the etching is missing, or a low quality or painted on the glasses will be.
If the etching is missing, or a low quality or painted on the glasses will be fake. On fakes the etching will either be missing or of poor quality. If the etching is missing, or a low quality or painted on the glasses will be fake.