Isabelle is one of the top five interactive theorem proving systems. It is used in numerous academic projects on formal theory development (Kepler Conjecture, Prime Number Theorem) and a few major industrial verifications (NICTA Verification of the L4 Kernel). Isabelle is jointly developed at University of Cambridge, Technische Universität München and Université Paris-Sud. The development at UPSud is focussed on the parallelization of the prover kernel and the development of asynchronous proof checking facilities and the development of new Prover IDE exploiting these features.
