The Virgule in the Middle
Such a punctuation mark has actually found its way on checks, and courts have had to interpret whether the mark means “and” or “or”. Big difference whether a check is payable to ABC and XYZ or to ABC or XYZ. And courts have determined that the use of a virgule is a manifestation of the drawer’s intent to make the instrument alternatively payable – a virgule is, in essence, a substitute for the word “or”.
Moreover, the Uniform Commercial Code, the bible for business transactions, states that when the issue of a check fails to use the words “and” or “or” then there is a presumption that the check is issued to alternate payees.
Now knowing all this, you may want to eliminate the virgule in the middle and use words that actually convey your intent.