According to the report's authors, this allows suppliers to maintain a significant market share in their original local monopolies - meaning they can keep their prices unnaturally high for customers who fail to switch.
Failing to change also allows open price coordination between suppliers, the report adds - as it goes on to claim that "these market conditions make it easy for all firms to keep prices well above costs without necessitating explicit collusion".
"There are now only six significant players and these companies share an interest in keeping prices well above costs," the study continues. "The less competition facing any one firm, the less that firm is inclined, or indeed is required, to compete."
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