A ballot shall be invalid if:
1. it is not completed or is completed in such a way that it is not possible to reliably ascertain for which political party, coalition, independent candidate, list of independent candidates a voter has cast his or her vote; or
2. names of candidates have been added in writing; or
3. more than one political party, coalition, or independent candidate or list of independent candidates has been marked; or
4. the voter can be identified based on markings added by the voter to the ballot, such as a signature; or
5. the voter marks the ballot in a manner other than as provided by Article 5.14 of the Law.