The phrase "are not considered valid" is correct and usable in written English.
It can be used when discussing the legitimacy or acceptance of something, often in formal or academic contexts.
Example: "The results of the experiment are not considered valid due to the lack of proper controls."
Alternatives: "are deemed invalid" or "are regarded as unacceptable."
Blood pressure will be validated within 2 days after delivery and measurements are not considered valid if >30% of the measurements are missing, or if not at least 20 measurements during daytime and at least 7 measurements during night time are obtained.
Tests conducted by the Russian anti-doping agency, which is suspended following repeated allegations of cover-ups, are not considered valid for Olympic purposes.
(Photo IDs aren't free, and obtaining them can be a hardship for working people, as well as individuals in rural areas who don't own cars. Student IDs are not considered valid for voting in some states).
According to the rules of nomenclature under the International Code of Nomenclature of Bacteria the body that governs the naming of prokaryotes valid taxa for bacteria extend from subspecies to class; taxonomic categories above class (e.g., phylum) are not considered valid.
A similar number of other potential subspecies have been proposed, but are not considered valid.
Jehovah's Witnesses do not practice infant baptism, and previous baptisms performed by other denominations are not considered valid.
Incidentally, a photocopy of your license, in part because it can be easily altered, is not considered valid identification.
She announced it at the time, but it was not considered valid until a tribunal judge confirmed it on Monday.
The elections were not considered valid by the Georgian central government, in part because ethnic Georgians in the region were denied the right to vote.
Her Christian marriage, in 2011, has been annulled and she has been sentenced to 100 lashes for adultery because the marriage is not considered valid under Islamic law.
