From Acidus on Curiouser and Curioser – USPA 0090132950 – IBM’s patent on input validation:

The present invention discloses a system for providing real-time validation of text input fields in a Web page during text entry. Such a system can include a validation-enhanced text input element and an input text validator. The validation-enhanced text input element can be configured to contain a validation expression for a text field in a Web page. The validation-enhanced text input element can be contained in the source code document that corresponds to the Web page. The input text validator can be configured to validate a character entered into the text field against the validation expression in real-time. Characters determined as invalid can be visually indicated by the input text validator in the text field.

Hurray for our busted ass patent system. As Acidus says, IBM, go fuck yourself. It may not be a patent on all forms of input validation (notice the reference to “real-time” – this seems to suggest an AJAX powered system to validate input fields as the user is typing), but really any patent on input validation is a freaking mistake by the patent office.

~ Joshbw