Capital gains for stocks purchased before Jan 2018

Gopi (Engineer) (123 Points)

23 June 2023  

I sold a few shares in last fiscal year, which were purchased much before Jan 2018.
For calculating capital gains, I used this:

 

Sale price - (market price as on Jan 2018) 

 

But my accountant this provision has been grandathered and I need to use the actual purchase price and not the market price on Jan 2018.
Is he correct?