Mithril underwent restructuring and its listing status was transferred to Pesona.
Consolidation of every 5 Mithril shares of RM0.05 each into 1 Pesona share of RM0.25 each.
Mithril last traded at RM0.10/ share before the transfer of listing status.
The reference price of Pesona was RM0.25/share, based on the face value of RM0.25 each instead of RM0.50/share, multiplying the last closing price of Mithril by 5. (Consolidation of 5 shares into 1)
More examples of calculation of theoretical ex-price for various corporate exercises here.