Abstract: The invention relates to a hydroxyl-functional polyester containing a perfluoropolyether block prepared by a method comprising the following steps: a) subjecting a carboxyl-terminated perfluoropolyether C to a reaction with an epoxy-functional compound D, and b) subjecting the reaction product of step a) to a reaction with a lactone E. The polyester thus prepared can be used in a coating composition, comprising further (b) an OH-functional or epoxy-functional resin, and (c) a hardener comprising groups reactive to the OH or epoxy-functional groups of resin (b).