The fourth chapter discusses limitations on ftc in u . s . internal law . the author considers that the basket - limitation system is the core of the current u . s . ftc limitation system and the main function of the basket - limitation system is to prevent taxpayers to cross - credit foreign taxes and to maintain u . s . tax jurisdiction over foreign source income as greatly as possible while maintaining u . s . taxation of u . s . source income 该章认为，美国现行抵免限额制度的核心内容为分篮限额制度，而分篮限额的主要功能在美国联邦所得税法外国税收抵免制度研究于，防止纳税人综合境外的高税率所得和低税率所得进行所谓的“交叉抵免” ，在维护美国对境内来源所得征税权的同时，最大程度地维护其对境外来源所得的征税权。
