Upper layer film forming composition, pattern forming method, resist pattern, and electronic device manufacturing method

This upper layer film forming composition forms an upper layer film by being coated on a resist film which is formed using actinic ray-sensitive or radiation-sensitive resin composition, and contains a resin X and a compound A having a radical trapping group. This pattern forming method involves a step a for forming a resist film by coating an actinic ray-sensitive or radiation-sensitive resin composition onto a substrate, a step b for forming an upper layer film on the resist film by a coating the resist film with the aforementioned upper layer film forming composition, a step c for exposing the resist film on which the upper layer film was formed, and a step d for forming a pattern by developing the exposed resist film using a developing solution that contains an organic solvent.