title: How to mark files in a GCP storage bucket as Read Only for "everyone"?
body: <p>We have a storage bucket which has sensitive data stored in it, in the form of JSON files. For a <a href="https://searchsecurity.techtarget.com/definition/PCI-DSS-12-requirements" rel="nofollow noreferrer">PCI</a> compliance, we have to make these files read only. <br>
  Versioning will be enabled on the bucket so <a href="https://cloud.google.com/storage/docs/bucket-lock" rel="nofollow noreferrer">Retention policy</a> can not be used. <br>
  I tried keeping only one account in the bucket permissions with Read Only access, that (not really) partially serves the purpose. But any user with Editor or Owner role can edit the file permissions and change it back to Editable and modify the file.<br>
  How to restrict anyone and everyone to not be able to edit or modify the file GCP?<br></p>
  
  <p>Is this technically possible with Google Cloud Platform?<br>
  If not, how to reduce access to a file as minimum as possible?</p>
  
  <p><strong>EDIT</strong> <br>
  I am not sure if we would compulsorily enable versioning, I will discuss this with the team (once they are available) and mention the same in the question.<br>
  So answers which consider "versioning will not be enabled" or ignore <a href="https://cloud.google.com/storage/docs/object-versioning" rel="nofollow noreferrer">versioning</a> completely, are also welcomed.</p>