The allottees of Residential, Commercial/Industrial who sell/transfer their lease property outside the blood relation for which lessor’s permission is required which is being given subject to charging of 50% Unearned Increase in the market value of the plot as per lease deed terms. In the following cases the unearned increase is not being attracted :

Conversion of partnership firm into a private limited firm comprising original partners as Directors.
Change from Pvt. Ltd. Co. to Public Ltd. Co.
In case of addition, deletion or substitution of partners in a firm or directors and conversion of sole proprietorship firm or partnership concern into private limited company when change in constitution is intimated, for approval by the DDA, within one year from the date of purchase of plot in auction. This will not apply in case of plot obtained by the party by way of allotment.
The cases in which unearned increase is being charged are as under :

Addition of outsider not falling within the family members.
Substitution of the original allottee/auction purchaser.
50% unearned increase is charged in respect of proportionate share of the plot parting with by way of addition, deletion or substitution of partner.
In the cases where a private limited company/public limited company separately floats a separate new company although directors may be the same.
The interest @ prevailing at the time of application on the unearned increase is charged from the date of receipt of application till the payment made by the allottee/company.

Source : DDA Website