Back in May, OPAP promoted Karas from CCO to acting CEO, replacing Damian Cope.
Initially, the executive was to assume all responsibilities except human resource duties from 1 June, until a permanent CEO was appointed.
However, Karas has duly been awarded the role on a full-time basis.
Kamil Ziegler, OPAP executive chairman, said: "On behalf of the board of directors, I would like to congratulate Jan Karas for assuming the CEO role.
"During the past period, Jan had been serving as OPAP’s acting CEO, contributing significantly to the company’s business initiatives, response to the COVID-19 pandemic and the impact of the relevant restrictive measures.
"We are looking forward to continuing working with him in his new capacity, to implement OPAP’s strategic objectives and address the challenges related to the recovery from the pandemic crisis."
OPAP's share price has shown a steady rise over the last month. Having dipped at $3.85 at the beginning of November, OPAP's stock value has since almost doubled to $6.38.