12 In the meantime, the United States had also concluded an agreement with West Germany, which was also pending until the adoption of the 1977 amendments.  2 An exception to this rule is the agreement concluded with Italy, which allows certain transferred workers to choose the social security scheme in which they are covered. No other U.S. tabination agreement contains a similar rule. The agreements work by assigning social protection and thus tax liability to a single country, as provided for in the rules of the agreement. These rules can vary greatly, but all agreements have some common characteristics, such as. B the allocation of coverage, so that workers pays social security taxes to one or the other country, and not to both. .