See the question and its resolution criteria on Metaculus: https://www.metaculus.com/questions/17682/putins-martial-law-declaration/

This question will resolve as Yes if Vladimir Putin officially declares a state of martial law covering 3/4 of all federal subjects of Russia before January 1, 2025. The declaration should be recognized and implemented by the Russian government through official channels and public announcements.

For the purposes of resolution, federal subjects whose territories are internationally recognized as part of Ukraine will not be considered in the 3/4 calculation.