I am a software designer by trait, and am working on a user interface, that depicts, amongst other things, the rate, by which a collection of serial numbers matches a group of patterns. It also shows matches and mismatches in total quantities; those fields I have called 'Validated' and 'Unvalidated' respectively. But it occured to me, that 'Unvalidated' probably expresses, that there wasn't an attempt made to validate the number, rather than an attempt failing. Long story short, if I wanted to keep using 'validate' as the root word, which prefix should I use to express a failed validation, and if there isn't such a thing, which word would be an elegant substitute?
I would prefer invalidated, as invalid actually means being without foundation in fact, true or law.
However, I perceive invalid number as something which is not a number at all.
Webster proposes better antonyms to validate: disprove, rebut, refute.