makesomegravy, I believe J_Livermore is fairly correct here. If your shares are held in a margin account, they are held in "street name" so the firm could sell them should you not meet a margin call. Since you've signed a hypothecation agreement and loan consent agreement when opening the margin account, any shares held in the account can be borrowed by your broker-dealer and loaned out to customers of the brokerage firm that desire to use the shares for short-selling purposes. Based on current regulations, customers aren't required to sign this agreement when signing up for an account.
I believe you can call your broker-dealer and tell them you'd like your shares sent to the particular company's transfer agent where he can hold the shares for you in book-entry form registered under your name (and not able to be shorted). Other than that, even if the shares are held in a cash account they could still be eligible to be borrowed by your brokerage firm if you've signed the loan consent agreement - you'll need to check with them.
By the way, the name is a moniker...I am no Colonel and its use is no way in a pretentious manner. A quick Google search on the name should reveal this.