I'd double check that, I believe if the stock is in a margin account, even if you have taken no margin, they can lend it without telling you it's lent. If you wish to vote the share, sell, etc. the shares are instantly restored and borrowed from someone else. If you have an agreement to be paid for lent shares, then you know if they're being lent.
Of course, you can probably prevent them to be considered in a margin account, but I'm not certain it won't cost you in other ways.
Gary
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