Other theorists reject the idea that the possessive in languages like English as represents a grammatical case since possessive forms do not generally behave in a parallel fashion to what are normally identified as cases. In particular, in English, as noted above, the -'s can attach to noun phrases even when they do not end with their head noun, as in the king of Spain's, which is not typical behavior for a case ending. For further discussion of the issue, see English possessive § Status of the possessive as a grammatical case.