SGH Price, page-85

I, a teacher, am here to attack bad grammar: "whoever he is" not "whomever he is."
It is Nominative Case (Subjective) not Accusative Case (Objective).
In any case, Usage says that the word "whomever" is being slowly but surely phased out, in the same way that '"thou" and "thee" and "thine" have been abandoned, quite a few centuries ago.

I attack bad grammar because I know very, very little about shares and that's about the only contribution I can make to these pages.

I'll take myself to the Principal's office now.