Related Clues:

• Mark indicates some of the letters are missing
• Bloomingdale's gets one out to a shopper
• An oft-mistaken sign of omission
• What you see with 'apple's'? It's upsetting to a shopper!
• An indication of possessiveness?
• Firm's structure has one but companies do not
• Perhaps too involved in punctuation?
• One's got one
• Because I won't be there, she's to be given it
• As old prophet might put it e.g., 'O Thou! -- whatever title suit thee ...'
• Greengrocers missing sign?
• Mark isn't included
• This gets carelessly misplaced -- perhaps too carelessly
• He's had to have one because I wasn't there
• It may be superfluous on tradesman's sign and idiotic too, perhaps