There has been a months-long, slow-motion edit war going on Wikipedia that involves the An-124-100M-150. If you are interested in the details, see the history of https://en.wikipedia.org/wiki/Antonov_An-124 although it's not really relevant to the question.
What exactly is the status of the -150? Information around the 'net is sketchy and mildly contradictory. One of the major features of the -150 over the base models is increased payload, and the issue is its ranking (in terms of size) relative to other large cargo aircraft, in particular the 748F.
Does this aircraft actually exist? And in a form where it can actually lift the advertised 150t? If it exists, has there been more than a single prototype produced? And is that prototype in actual use?
There are repeated mentions that there is a -150 in development, although I've not seen any reference to actual serial production. Even the Antonov site barely mentions the -150 in passing.
OTOH, there exist at least a few images of an aircraft with "-150" painted on the side.
And links would be good.