Transfer of flat in chs of mumbai

While submitting Application for transfer of a Flat in Co Operative Housing Society in Mumbai, is it still necessary for the Seller and the Purchaser of the Flat to sign and execute the Form of Declaration for not holding immovable property in any urban agglomeration under ULC Act? and if yes, does the Seller and the Purchaser has to make such Declaration on Rs. 100/- Stamp Paper?