Does case sensitivity matter when filtering out urls?

www. as well

[GameFridge]

Does it matter if I write a url I want to block as say www.inserturlhere.com or does it have to be written the way it is shown, such as www.InsertURLhere.com
Also do I have to drop the www. if the url doesn't show it?

[amznVibe]

Leave the "www." off if you want to match with or without.

Google will lowercase any uppercase or mixed-case entry when adding it and overwrite any existing filter that is the same.

In fact that is a good tip to others, if you are tired of getting the red warning that it's a duplicate when adding filters, simpy change the case of one of the letters and google will overwrite any exisitng entry that is identical without warning (if you don't want to know).

Example.com
eXample.com

will be changed to example.com
and also block www.example.com

Now if there is a vendor using www.example.com and another vendor using example.com and you enter www.example.com you only block the first one.

However note that vendors change their urls from time to time.
You must be vigilant in watching for these changes.