Can the printers be regulated to refuse to print weapons, or could new designs simply circumvent existing prohibited products?

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So in 1989 the international sale of new ivory products was prohibited.

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For years, agreements that retailers have signed with third-party payment processors prohibited merchants from selling products at different prices depending on payment method.

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The process resembles the hunt for performance enhancements used by athletes, where a few get caught but the cleverer ones stay ahead by using products not yet on the prohibited list.

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Then, in May, the Pentagon's Defence Contract Management Agency announced an inquiry into allegations that the company was violating the (aptly-named) Berry amendment, which has prohibited the use of foreign materials in products bought by the Department of Defence for more than 50 years.

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The reason is simple: drug companies are prohibited from pro-actively sharing information about their products for uses beyond what the FDA has approved.

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In his reply to Senator Rockefeller, Mr. McCurdy carefully noted that as products became available under the program, antitrust laws prohibited the companies from joining together and choosing one product over another.

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As set out in FIFA's equipment regulations, all advertising for "tobacco-related products, gambling establishments (casinos), and alcoholic beverages" is prohibited.

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