The knock on NOCs
About 77 percent of the world's 1.1 trillion barrels in proven oil reserves is controlled by governments that significantly restrict access to international companies, according to PFC Energy, an industry consulting firm in Washington.
So reports Justin Blum in the Washington Post: "National Oil Firms Take Bigger Role: Governments Hold Most of World's Reserves" (August 3, 2005; Page D01).
That restricted access and the desire of governments to limit knowledge of their holdings is why we typically and consistently underestimate the world's supply of oil (funny how they always seem to find more in such disconnected venues when the price rises. ..). When foreign companies are let in, they find more oil, but NOCs (national oil companies) are loathe to do that. Like most national companies, they prefer a smaller pie they can control completely to a larger one they can't dominate.
Full story found at: www.washingtonpost.com/wp-dyn/content/article/2005/08/02/AR2005080201978.html.
Story also notes that CNOOC dropped its bid for UNOCAL. A setback of sorts, but not a showstopper. China's energy needs don't go away just because a few dinosaur U.S. congressman demand it. This was just an opening bid.
For a solid bit of analysis on that, see Keith Bradsher's "China Retreats Now, but It Will Be Back" (New York Times, 3 August 2005).