I was checking a SIGN credential earlier across two networks.
Didn’t expect anything unusual.
It passed on the first one.
Clean.
Then I verified the same credential on another network.
It failed.
At that point I thought I missed something obvious.
Pulled it again.
Same result.
Didn’t make sense.
Nothing had changed.
No revocation.
No update.
Same credential.
So I slowed it down.
Checked where it was issued.
Then where it was being verified.
`validUntil` was still in range.
But only on the network it came from.
On the second network...
it had already crossed the boundary.
That’s when it stopped feeling like a mistake.
And started feeling structural.
The credential wasn’t moving.
The reference point was.
I expected the credential to carry its own reference.
It didn’t.
Everything was being resolved at the moment of verification.
And that moment... wasn’t the same everywhere.
Chain time drift.
The credential stayed the same.
The network didn’t agree on time.
I ran more checks after that.
Different credentials.
Different schemas.
Same pattern.
Validity wasn’t fixed.
It depended on where you checked it.
At first it just looked off.
Like something didn’t line up.
But it wasn’t random.
It was directional.
Each network was internally correct.
They just weren’t aligned with each other.
That’s where it starts to matter.
An access system verifies through SIGN on one network... and grants entry.
Another system verifies the same credential somewhere else... and denies it.
Same credential.
Different outcome.
No dispute.
No signal.
Just two systems... trusting different answers.
Nothing fails loudly.
It just diverges.
And because both sides resolve cleanly...
there’s no signal that anything is wrong.
I kept expecting something to reconcile it.
Some shared reference.
Some anchor point.
Didn’t find one.
Everything resolves locally.
At verification.
Using that chain’s sense of time.
Which means “now” isn’t global.
It’s contextual.
And once that’s true...
validity isn’t absolute anymore.
$SIGN only matters if `validUntil` can stay consistent across networks...
even when each one defines “now” differently.
So the real question becomes this.
If the network can’t agree on time
what exactly is “valid” measuring anymore?