On the (Im)possibility of Obfuscating Programs The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters

are not ne essarily omputable in polynomial time, (b) only approximately preserve the fun tionality, and ( ) only need to work for very restri ted models of omputation (TC0). We also rule out several potential appli ations of obfus ators, by onstru ting \unobfus atable" signature s hemes, en ryption s hemes, and pseudorandom fun tion families.