[cynwoody]

Once it's leaked, it's not classified information. It is merely public information

The guilty party is the leaker, who was legally bound to secure the information.

Subsequent propagators and consumers of the information are blameless.

[ReaganGeneration2]

You’re correct:
No law exists for those not having clearances. The uncleared have no way to discern if a document is classified - and markings are not enough. If a law was created, welcome to a worse tyranny than we already have here.

However, if leaked to the public, a document’s classification status doesn’t change.

[antidisestablishment]

“Once it’s leaked, it’s not classified information.”

This is not the case at all. The originating authority makes the determination when something is declassified. A leak changes nothing and individuals can lose their clearance for accessing such (illegal) “public” information.

That said, absent malice, the press is not liable for what they publish; however leakers should be unless they are have exhausted all legal recourse.

Then again, Seth Rich may have had a different idea...

[markomalley]

Once it's leaked, it's not classified information. It is merely public information

ABSOLUTELY NOT TRUE.

See this from DoD 5200.01-M Vol III:

It is still classified until, after a review by the OCA, the OCA determines that there is no purpose in keeping it classified.