http://www.insidescience.org/research/study_says_world_s_stocks_controlled_by_select_few A recent analysis of the 2007 financial markets of 48 countries has revealed that the world's finances are in the hands of just a few mutual funds, banks, and corporations. This is the first clear picture of the global concentration of financial power, and point out the worldwide financial system's vulnerability as it stood on the brink of the current economic crisis.
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The most pared-down backbones exist in Anglo-Saxon countries, including the U.S., Australia, and the U.K. Paradoxically; these same countries are considered by economists to have the most widely-held stocks in the world, with ownership of companies tending to be spread out among many investors. But while each American company may link to many owners, Glattfelder and Battiston's analysis found that the owners varied little from stock to stock, meaning that comparatively few hands are holding the reins of the entire market.
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“If you would look at this locally, it's always distributed,” Glattfelder said. “If you then look at who is at the end of these links, you find that it's the same guys, [which] is not something you'd expect from the local view.”
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Glattfelder added that the internationalism of these powerful companies makes it difficult to gauge their economic influence. "[With] new company structures which are so big and spanning the globe, it's hard to see what they're up to and what they're doing,” he said. Large, sparse networks dominated by a few major companies could also be more vulnerable, he said. "In network speak, if those nodes fail, that has a big effect on the network."