January 3, 2006: China has produced a new twin 23mm antiaircraft gun that, apparently uses stolen American technology. The Chinese describe their new antiaircraft system as using "Chain Gun" technology. The U.S. Boeing company holds patents on the chain gun feed mechanism. In 2001, China first mentioned that they had adopted the "chain gun" technology, but at the time, these weapons were only available for Chinese use. Now that the Chinese are selling new versions of these weapons to foreigners, Boeing may go after them for patent infringement. Boeing tried to sell the Chinese chain gun technology in the 1990s, demonstrating it in China. But there was no sale. Why buy when you can steal?