The current rules for update around tags are as follows:

"The server stores all the tags provided in the headers, and keeps any tags already associated with the resource"

However, some update operations may invalidate tags. For example a "reviewed by clinician" tag on a lab result would be invalidated if the lab result were corrected. Similarly, some security tags might be invalidated when the resource content is updated. Suggest adding the following to the existing rule text:

"In some cases, an update may invalidate existing tags. Servers may update or remove previously existing recognized tags if this is known to be appropriate."