Two insurance companies representing former hedge fund giant Steven A. Cohen have filed a lawsuit against a company whose workers caused a fire that destroyed an unknown amount of his art collection.

The November 2015 fire at the Stamford headquarters of Cohen’s Point72 Asset Management Co. was confined to the roof but there was some water damage in the building, primarily to the pantry area on the second floor. What was not reported or known at the time was that art owned by Cohen was inside the building and damaged in the blaze, according to the lawsuit filed Wednesday.