NRIs are allowed to invest in shares of listed Indian companies in recognised Stock Exchanges under the PIS. However there is a ceiling. These limits are mentioned below: -
a. NRIs can invest through designated ADRs, on repatriation and non repatriation basis under PIS route up to 5 per cent of the paid- up capital / paid-up value of each series of debentures of listed Indian companies.
b. The aggregate paid-up value of shares / convertible debentures purchased by all NRIs cannot exceed 10 per cent of the paid-up capital of the company / paid-up value of each series of debentures of the company.
c. The aggregate ceiling of 10 per cent can be raised to 24 per cent, if the General Body of the Indian company passes a special resolution to that effect.
Know more about NRI Investments at Upstox Knowledge Base.