Blank forms are not in general terms protected by copyright law. Even if the form has a lot of design flourishes, it's still considered a tool to collect data.
Some elements of the form may hold copyright in and of themselves, for example:
- a logotype element on the page may have protection via trademark
- a graphical design element or photograph may have standalone copyright
- a block of original text used on the form (by way of explanation, etc.) can be considered a copyrightable work in isolation provided it meets the standards to be considered a creative work, but plain statements of fact such as field labels or button tooltips are not.
but the form itself is not a "creative work". The same is true of things like blank diaries, bank checks or sheets of headed notepaper.
The answer depends a lot on the country you live in and, if different, the county your users reside in. In the end, you will probably need a lawyer to get a reliable answer.