INPP has issued ordinary shares of 0.01p each through corporate broker Numis Securities to raise approximately £80m.
INPP has recently invested £88m into the Reliance Rail PPP Project in Australia, with a further £14m expected to be drawn by the end of the year for committed investments into the Victoria Schools, Gold Coast Light Railway and the Thames Tideway Tunnel projects.
The investor also announced earlier this week that it was selected as preferred bidder for the Dudgeon OFTO project, in which it expects to invest about £50m upon financial close towards the second quarter of 2018.
The raising operation has already started, with receipt of commitments due by 5 December and results expected the following day.