The Investment Funds Institute of Canada reports that Kentucky, Maryland and Vermont have been added to the list of U.S. states with at least some form of legislation or policy that permits Canadian brokers/dealers to deal with clients in those states.
IFIC has posted an updated survey that outlines the requirements for each state. It says a Canadian broker-dealer may receive an exemption from registration in Kentucky if it only effects transactions for: a Canadian resident temporarily resident in the state; or a Canadian resident whose transactions are in a Canadian self-directed tax-advantaged retirement plan; among others.
A similar exemption is now available in Maryland and Vermont.
Generally the Canadian broker-dealer must be a member of a self-regulatory organization or stock exchange in Canada, it must have no local presence, it must have a pre-existing relationship with the client.