From Longman Dictionary of Contemporary Englishwho says?who says?DISAGREEused to say that you do not agree with a statement, opinion etc Who says museum work doesn’t pay? → say
Examples from the Corpus
who says?• Pike, who says his legal past is irrelevant to the business venture, has been reluctant to surrender full control.• I know another guide who says she has a different umbrella for every outfit she owns.• She is young but not so young as Chela, who says she is 18 but looks 16 at the most.• This is also the same guys who says so Peter works graveyard shift, huh?• Who says Tommy and I are still going out?