Company's earnings before interest, tax, debt and amortisation (EBITDA) came in at 594 million crowns ($69.24 million), compared with a loss of 13 million crowns in the year-ago period.

Okea produced 20,045 barrels of oil equivalent per day (boepd) in the second quarter, up from 358 boepd a year ago.

The Norwegian company, which was listed on the exchange in June, is part of a crowded pipeline for stock market flotations in the European oil sector. It is majority owned by Thailand's Bangchak Corporation and private equity firm Seacrest Capital.

Oil and gas companies with a combined value of around $41 billion are seen as candidates for listing in the coming years, according to estimates by energy consultancy Wood Mackenzie.