Traditionally the world looked to the United States for lessons on how to run a state-of-the-art stock market. But the decline of small-business listings suggests that America may do well to look for advice from some of its former students. Ironically, it may be the most antiquated exchange that offers the clearest guidance.

Of course, the United States is not the only global market to see a drying up of small-cap public offerings. Even exchanges that specialize in making life easy for such businesses have been struggling. By the end of 2011, the number of companies listed on London’s Alternative Investment Market was at its lowest level in seven years.

“There are tentative signs that this IPO disease has been spreading to Europe too,” says Colin Mason, a business professor at the University of Strathclyde in Glasgow and author of a report on the subject for the City of London. “Various mature markets look to be seeing this.”

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