PIS or Portfolio Investment Scheme is a scheme by RBI to allow non-resident Indians to purchase and sell shares listed on the Indian stock exchanges; BSE and NSE.
RBI has allowed only certain designated bank branches to provide PIS permission letters to NRIs on their NRE or NRO accounts. An NRI customer who has opened a PIS account in India can invest in listed Indian equities. All the transactions placed through the PIS account are reported to RBI.
The PIS account facilitates NRI investment in India on a repatriation or non-repatriation basis. NRI can open an NRE (Non-Resident External) account and get a PIS letter to execute transactions on a repatriation basis while NRO (Non-Resident Ordinary) account can be opened to purchase and sell shares on a non-repatriation basis.