The Rs.500 note with green security thread closer to Mahatma Gandhi picture is a fake note
The security thread appears to the left of the Mahatma's portrait. Security thread has a plain, non-readable fully embedded security thread. But since October 2000, the Rs.2000 notes contain a readable, windowed security thread alternately visible on the obverse with the inscriptions ‘Bharat’ (in Hindi), ‘2000’ and ‘RBI’. All the currency notes have security thread. When notes held against the light, the security thread on Rs.2000, Rs.500 and Rs.100 can be seen as one continuous line. [...] On the obverse side of Rs.2000, Rs.500, Rs.100, Rs.50 and Rs.20 notes, a vertical band on the right side of the Mahatma Gandhi’s portrait contains a latent image showing the respective denominational value in numeral. The latent image is visible only when the note is held horizontally at eye level.