When is a big business a small business?

When is a big business a small business? Apparently, when there are federal government contracts at stake. The New York Times has an article today (subscription required) asserting that last year, at least $4.9 billion worth of contracts, earmarked for small businesses, went to 13 of the largest government contractors. According to the Times, "For years, government studies show, large corporations like GTSI, Boeing, General Dynamics and Northrop Grumman have been counted as small businesses either through legal loopholes, via acquisitions or simply by mistake. And despite some efforts by the federal government to correct the mistakes, problems persist."