Yes, I read years ago, in multiple places, that if

Yes, I read years ago, in multiple places, that if you "lock up" your shares in a "good until executed" or "good for 60 days" trade, you can stop your shares from being "loaned out" for short sellers to use.

I haven't looked into that for verification recently, but I suspect it can stop the legal shorting, just not "naked" shorting. Put that ask price as high as your brokerage house will let you just to be safe. Etrade let me put an ask of $5/share, as did another broker in another acct I have.