Buy-back of physical shares requires a separate exchange window and broker verification, priced by volume-weighted average market price. Regulation 15A requires buy-back of physical shares through a separate stock exchange window where brokers must verify identity and address proofs; pricing is the volume weighted average price of securities bought back in the calendar week when the broker received them, or the preceding week if no market buy-backs occurred, with a specific reference for tenders in the first calendar week to the preceding week's volume weighted average market price.