I guess, you are asking regarding taking prior permission of the Institute for transfer of articleship. In that case, you need to send your application to
"Sr. Asstt. Secretary at "lCAl Bhawan", 122, Mahatma Gandhi Road, Post Box No. 3314, Nungambakkam, Chennai-600 034."
Please note that prior permission is not required for transfer of articleship during the first year of your articleship.