The British-Iranian businessman acquired a 49.9 per cent stake in Everton two years ago.
And Moshiri, a former Arsenal shareholder, has now invested further in Everton, the club confirmed in a statement on Tuesday.
"Farhad Moshiri previously owned 49.9 per cent of the club and in line with the agreement made at the time of his original investment, he has purchased 18.7 per cent through Blue Heaven Holdings," Everton said.
Moshiri now has a total holding of 68.6 per cent and Everton said this "is expected to increase to 77.2 per cent no later than July 2019".
Everton invested heavily in their squad during the transfer window, bringing in players including Richarlison, Yerry Mina, Lucas Digne, Bernard and Andre Gomes.