We are happy to announce the release of Spot 2.6.3 This is a maintenance release containing only bug fixes. You can find the new release here: http://www.lrde.epita.fr/dload/spot/spot-2.6.3.tar.gz See https://spot.lrde.epita.fr/ for documentation and installation instructions. As always, please direct any feedback to <spot@lrde.epita.fr>. New in spot 2.6.3 (2018-10-17) Bugs fixed: - Running "ltl2tgba -B" on formulas of the type FG(safety) would unexpectedly use a co-Büchi automaton as an intermediate step. This in turn caused "ltl2tgba -U -B" to not produce unambiguous automata. - ltl2tgba --low now disables the "gf-guarantee" feature, as documented. - ltlfilt's --accept-word and --reject-word options were ignored unless used together. -- Alexandre Duret-Lutz