The group now explores, develops and produces oil and gas in Papua New Guinea and Australia, not to mention Yemen, Libya, Iraq and Tunisia.
OSH was one of the hot shares in 2010, rising from around $5 earlier in the year to a high around $7.10 in December.
On 22 February, OSH reported its FY10 results, including net profit after tax (NPAT) including significant items of US$185.6 million, a 39% increase on-year.
2010 total oil and gas production was 7.7 mmboe, 6% lower than in 2009 but above market guidance.
Lower production reflected natural decline from the mature PNG oil fields, offset by production from recent successful development drilling, the optimisation of existing wells and facilities and a significant reduction in unplanned plant and well downtime.
Driving the profit result was a 23% rise in the average realised oil price and a one-off restatement of deferred tax, which more than offset 7% lower oil sales volumes.
Excluding significant items, NPAT rose 45% to US$144.1 million, whilst OSH declared a total dividend for the year of four US cents per share, flat on 2009.
OSH also confirmed that the famed PNG LNG project is looking at first gas in 1H14.