Trade Compensation with Retained

If an NHL team A trades Player A to NHL Team B and retains 50% of Player A's salary, does the NHL require that NHL Team A be compensated in some way by NHL Team B? For example, if St. Louis trades Parayko to Toronto and retains 50% of his salary, is Toronto required to give St. Louis draft pick compensation, a player, etc., in exchange for St. Louis retaining 50% of Parayko's salary, or could St. Louis just trade Parayko to Toronto, retain 50% of his salary and only get "considerations" in the deal?