ORIGIN Energy has finalised the purchase of two offshore exploration permits in Western Australia’s Browse basin, leaving Karoon Gas Australia’s bank balance US$600 million heavier.

The purchase of Karoon’s 40 per cent interest in WA-315-P and WA-398-P enables Origin to establish “a strategic position in one of Australia’s largest recent offshore gas discoveries,” the company said.

It complemented its recent farm-ins in the Cooper and Beetaloo basins and the awarding of new exploration acreage in the Bonaparte basin, Origin added.

In addition to the upfront US$600 million payment Karoon received, a further reimbursement of back costs associated with the Pharos-1 well will be received in the coming weeks.

Origin will later pay US$75 million when a final investment decision is made and another US$75 million on first production, with another US$50 million payable if first production reaches a certain threshold.