Talked with an Ameritrade Supervisor regarding PCFG shares early last year. I was considering changing to a Margin account from a Cash account.
"How do I keep my shares from being borrowed and shorted"? His reply, a cash account. He gave me a verbal, "if you don't borrow on margin, we won't borrow your shares to short". So I went margin.
I asked him, "how do I know shares in my account are legit and not naked short shares"? He wrote me a letter stating they guaranteed all shares in my account are legit.