The part that does this is not FlexLM itself, but safecast with which it is frequently bundled, but many specialized engineering products use only FlexLM withou

The part that does this is not FlexLM itself, but safecast with which it is frequently bundled, but many specialized engineering products use only FlexLM without additional DRM layer (FlexLM itself is originally meant for Unix and mostly portable, Safecast is probably Windows-only). On the other hand many things use FlexLM only to provide node-locking which is thing that it can do, but is to some extent an afterthought. The thing was originally designed to be used over network to provide floating licensing, with some minimal resistance to cheating and cracking. In fact it seems that it's original author(s) (wikipedia says that the whole "team", but it mostly looks like one guy) got fed up with managment and marketing so much that he went on to implement and sell RLM on their own, which mostly seems like slightly better FlexLM without completely nonsensical features.