Csányi's Sertorius Global Opportunities Fund bought 115,000 shares at an average price of HUF 10,770 per share.
A day earlier, the fund bought 100,000 shares at an average price of HUF 9,767 per share.
OTP shares traded over HUF 18,000 early in February, before the start of the war in Ukraine.
The lender has exposure in both Ukraine and Russia.