Thanks Travis, I'll give it a try likely tomorrow. Rick USA ----- Original Message ----- From: Travis Roth To: program-l@xxxxxxxxxxxxx Sent: Sunday, October 07, 2012 9:35 AM Subject: [program-l] Re: Regular Expression Question Hello Rick, The current expression would match more than one period because the expression is not ended, e.g., the $ sign is not used to say additional matching is not allowed. According to your specifications (only for upper case letters) this should work. ^[A-Z][A-Z]*[\-\.]?[A-Z]*$ From: program-l-bounce@xxxxxxxxxxxxx [mailto:program-l-bounce@xxxxxxxxxxxxx] On Behalf Of RicksPlace Sent: Sunday, October 07, 2012 3:43 AM To: program-l@xxxxxxxxxxxxx Subject: [program-l] Re: Regular Expression Question Hi Travis: The slash was a mistake since this is a .net app. What I am trying to do: Ensure the first character is a letter (Case should not matter or I can enforce upper case as i did in my test expression) There may be no special characters in a ticker symbol like: MSFT or KMI or PPG Or there may be one period in a ticker symbol like: MSFT.OB or PPG.XYZ There can not be more than one period if there are any in the ticker. This would be invalid MS.FT.OB as there are 2 periods as would be MS..FT or MSFT.. two periods are not allowed only 0 or 1. Finally there can be 0 to 1 dashes like: MSFT-BB or even MSFT-BB.OB. Again MS-FT-OB would be bad because of 2 dashes in the string. No other characters are allowed in the string only letters, perhaps one period and, or, perhaps one dash. I couldnt get the filters to work yesterday so just checked the first character to ensure it was a letter - that worked. I think the [A-Z] also works but the \. allowed more than one period like: MS..FT or MSFT..OB Rick USA