From the opinion:
So, apparently, partial registration is okay as long as it doesn't cover the entire nation.....The ATF’s reporting demand from about 8,500 dealers in Texas, California, New Mexico and Arizona “required information on only a small number of transactions” and “does not come close to creating a ‘national firearms registry,’” U.S. Circuit Judge Karen LeCraft Henderson wrote in the 30-page opinion.
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http://www.bloomberg.com/news/2013-05-3 ... cmpid=yhoo