We’ve just found (and fixed) a no-loop bug. https://issues.jboss.org/browse/DROOLS-353 In general we recommend @PropertyReactive over no-loop (and lock-on-active), for best practice. If you hit this bug, which is caused by a modify, and you cannot migrate your stuff to @PropertyReactive you can fall back to using ReteOO mode for your execution. Or use our latest SNAPSHOT builds from master. As mentioned this is fixed and will be in the next binary release - but that will not likely happen until january(guesstimate) now, as our time is focused on preparing the BRMS 6.0 product release. Mark