Shareholders for the British-based BG Group paved the way for the biggest energy merger in more than five years the other day when they approved the acquisition of their oil and gas company by Royal Dutch Shell for $50 billion.

When Shell announced plans for the takeover last April, the proposed deal was widely seen as a possible harbinger of mergers and acquisitions across the industry.

But aside from an earlier and still pending bid by the oil service provider Halliburton to buy one of its rivals, Baker Hughes, for $35 billion, no such trend has emerged, despite the plunge in oil prices that has taken place over the last 18 months and its devastating impact on many companies. (Read More)