Back on September 2014, the bond rating agency Fitch decided that SHLD wasn't even worthy of a 'CCC' rating, but gave them a 'CC' rating. That rating was affirmed yet again in January 2017.
2014 article: https://www.barrons.com/articles/fitch-downgrades-sears-to-deepest-junk-ratings-1410375408
2017 article:
https://www.reuters.com/article/idUSFit987711