From the catalog of Sotheby's November 1858 auction of the Whittall collection:
Great care has been taken to exclude false coins; but if any coin should be suspected at the time of sale, it is to be withdrawn, as Mr. Whittall will not consent to sell as false what he is confident to be genuine. This observation applies also to Lot 293, in which instance alone the writer differs from his employer as to the authenticity of any coin contained herein.
Lot 293 was a tetradrachm of Tenos similar to
this one.
I don't know who served as cateloger for Sothehby's in the 1850s. He must have held a great deal of power. I can't imagine a modern coin dealer allowing an employee or contractor to publicly doubt his counterfeit-spotting eye in the dealer's own catalog!
I do not know what the lot sold for. There is a '1' printed next to it; I assume that is the estimate, £1. The lot description itself repeats the warning, being followed with “⁂The authenticity is left to individual opinion.”