Formula not working in my spreadsheet

Hi.  I have a spreadsheet which I use to follow different stocks.  I am having problems with one of my formulas.  It gives me incorrect results, which messes up my list of stocks that I am looking for.  I have attached a part of the spreadsheet which contains the non-working formula.  Any thoughts on how to fix this.  The cell in question is A12.  It is an indicator which identifies stocks for me.  Cell A11 is showing blank, as it should, but Cell  A12 seems to think otherwise.  Thank you for looking.