Novel polymerizable ester compounds having formulae (1) to (4) undergo no acid-induced decomposition by .beta.-elimination wherein A.sup.1 is a polymerizable functional group having a carbon-carbon double bond, R.sup.1 is H or --C--(R.sup.5).sub.3, R.sup.2 and R.sup.3 are alkyl, R.sup.4 is H or alkyl, R.sup.5 is a monovalent hydrocarbon group, X is alkylene, Y is methylene, ethylene or isopropylidene, Z is alkylene, and n=1 or 2. Resist compositions comprising polymers derived from the ester compounds have excellent sensitivity and resolution and lend themselves to micropatterning lithography. ##STR00001##