Would any taxability arise if an immovable property is received for less than its stamp duty value?
If an Individual or HUF receives (on or after 1st day of October, 2009 but before April 1, 2017) and any person receives (After April 1, 2017), in any previous year from any person or persons any immovable property(being land or building or both):

without consideration, the stamp duty value of which exceeds Rs. 50,000 then the stamp duty value shall be chargeable to tax.
for a consideration, if stamp duty value exceeds the amount of consideration and the difference between stamp duty value and consideration is more than Rs. 50,000, then such difference is chargeable to tax. (applicable from A.Y 2014-15 to A.Y 2018-19).
for a consideration, if stamp duty value exceeds 110%* of the amount of consideration and the difference between stamp duty value and consideration is more than Rs. 50,000, then such difference is chargeable to tax.
Provided that where the date of an agreement and date of registration are not same, Stamp Duty will be considered as applicable on the date of agreement. This will be applicable only when the amount of consideration is received by account-payee cheque or bank draft or online transfer or through such other electronic mode as my be precribed before the date of agreement.
Provided that if the stamp duty value of immovable property is disputed by the assessee on grounds mentioned in sub-section (2) of section 50C, t​he Assessing officer may refer the valuation of such property to a Valuation Officer, and the provisions of section 50C and sub-section (15) of section 155 shall apply in relation to stamp duty value of such property as they apply for valuation of a capital asset under those sections.
* To boost the demand in the real-estate sector and to enable the real-estate developers to sell their unsold inventory at a lower rate, the safe harbour limit is increased from existing 10% to 20% in case of transfer of residential property during the period from 12-11-2020 to 30-06-2021 by way of the first-time allotment to any person. Further, the consideration received or accruing as a result of such transfer should not exceed Rs. 2 crores