Quick answer
Check the wire itself, not the packaging. On a genuine product the following is printed continuously along the insulation:
- Manufacturer and product name
- Size in sq mm and voltage grade (1100 V)
- The applicable standard (for example IS 694 or IS 17048)
- The ISI mark with a BIS licence number in the format CM/L-XXXXXXX
Printing on the insulation is far harder to counterfeit than a sticker or a printed drum label, which is exactly why reputable manufacturers do it. If the licence number appears only on the packaging, treat that as a warning sign.
Every APAR wire carries its grade, size, voltage, standard and BIS licence number printed along the insulation.