Combating BDS Act of 2017 This bill allows a state or local government to adopt and enforce measures to divest its assets from, prohibit investment of its assets in, or restrict contracting with: (1) an entity that engages in a commerce- or investment-related boycott, divestment, or sanctions activity targeting Israel; or (2) an entity that owns or controls, is owned or controlled by, or is under common ownership or control with such an entity. Such measures are not preempted by federal law. A state or local government that seeks to adopt or enforce such measures shall comply with specified requirements related to notice, timing, and opportunity for comment. In addition, the bill amends the Investment Company Act of 1940 to prohibit a person from bringing any civil, criminal, or administrative action against a registered investment company based solely upon that company's divestment from securities issued by a person that engages in a commerce- or investment-related boycott, divestment, or sanctions activity targeting Israel.