The champagne bottles will be chilling at Santos headquarters in Australia as it prepares to celebrate the acquisition of Oil Search, but it will be a sad exit for the trailblazing Papua New Guinea national hero.

Full credit to Santos, which saw the opportunity and pounced, but of course it happened so soon after legendary founding managing director Peter Botten had retired.

Would the takeover have happened if Botten were still in charge? Definitely not, Oil Search sources tell Upstream.

Botten had good relations with his shareholders and was particularly attentive to his PNG shareholders. If a takeover made sense, at the very least his shareholders would have received a better price, sources tell us.

Botten had power and persuasion over his board of directors, whereas his replacement, Keiran Wulff, did not.

When Santos made its initial offer in June this year, Wulff was not impressed, according to Oil Search sources.

A few weeks later, in mid-July, Wulff resigned. It was a shock announcement, with Oil Search citing "concerns and complaints" about his behaviour.

With Wulff and Botten gone, the Oil Search board was unencumbered to support the takeover.

And sure enough, the merger has progressed smoothly through the various gates, meeting little resistance in PNG.

The country's deputy prime minister expressed concerns about the devaluing of PNG's capital markets and local shareholders being cast adrift, but Santos has made commitments to address these concerns, including no PNG-based job losses.

Grant Samuel, the independent expert who assessed the offer, suggested that Oil Search shareholders would be contributing a greater proportion to the underlying value of the merged company than the 38.5% stake they would receive, but recommended the merger due to other benefits.

To the victor go the spoils: excellent cash flows and great projects. To be fair, Santos, under chief executive Kevin Gallagher, has become a good company, and could now become a great one.