Photoresist topcoat compositions, comprising: a first polymer comprising a first repeat unit of general formula (I) and a second repeat unit of general formula (II): wherein: R1 independently represents H, F or optionally fluorinated C1 to C4 alkyl; R2 represents optionally fluorinated linear, branched or cyclic C1 to C20 alkyl; L1 represents a single bond or a multivalent linking group; and n is an integer of from 1 to 5; a second polymer comprising a first repeat unit of general formula (III) and a second repeat unit of general formula (IV): wherein: R3 independently represents H, F or optionally fluorinated C1 to C4 alkyl; R4 represents linear, branched or cyclic C1 to C20 alkyl; R5 represents linear, branched or cyclic C1 to C20 fluoroalkyl; L2 represents a single bond or a multivalent linking group; and n is an integer of from 1 to 5; and a solvent. Coated substrates coated with the described topcoat compositions and methods of processing a photoresist composition are also provided. The invention finds particular applicability in the manufacture of semiconductor devices.