Not mine either, but why not? "We have shown X during the tour. Joe and Mary certify that. The article mentions X. This is a violation of the NDA." Even if X

Not mine either, but why not? "We have shown X during the tour. Joe and Mary certify that. The article mentions X. This is a violation of the NDA." Even if X was common knowledge, once you sign the agreement, you're setting yourself up for trouble if you do something you agreed not to.