3[(d) in the case of a capital asset, being a share or any other security (hereafter in this clause referred to as the financial asset) subscribed to by the assessee on the basis of his right to subscribe to such financial asset or subscribed to by the person in whose favour the assessee has renounced his right to subscribe to such financial asset, the period shall be reckoned from the date of allotment of such financial asset ;
(e) in the case of a capital asset, being the right to subscribe to any financial asset, which is renounced in favour of any other person, the period shall be reckoned from the date of the offer of such right by the company or institution, as the case may be, making such offer ;]
4 [(f) in the case of a capital asset, being a financial asset, allotted without any payment and on the basis of holding of any other financial asset, the period shall be reckoned from the date of the allotment of such financial asset ;]
above reference is for bonus issue, right issue and right entitlements
refer section 2 definations on income tax department website