Very common, especially in the name of the HBC. Preceding components of that name display remarkable variation, so most of those will probably end up being done manually. Regexps:

(?<!abbr>)([C])([o]?<hi rend="[^"]+super+[^"]+">y\.?</hi>\.?)
<choice><abbr>$1$2</abbr><expan>$1ompany</expan></choice>