Validation controls are fired by a button in a GridView. How do I prevent this?

 I have a web form that contains many text box controls requiring user input. I am using the .NET validation controls
to validate user input. The web form works great.
A new requirement has resulted in me having to add a GridView control to the page. The GridView control has a button
in one column. The problem is that when a button on the GridView is pressed, it is causing my webform to validate all
user input for the text box controls outside of my GridView.  How do I prevent the button in the GridView from
causing it to validate all controls on the page?
I looked in my code behind file and I am never making a call to   the Page.Validate() method.
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