If you've followed Inkan you know the core trick: your signing key gets compromised, you revoke it, swap in a new one, and you keep your identity and your followers. Key dies, identity survives.
But there was one gap left.
Say your key gets stolen Saturday 4:39am. You don't notice. You wake up, post a few notes, run errands. It's now Saturday 3:19pm you finally see something's off and revoke the key. That's great, but for 10½ hours the thief held a valid signer key. Anything they posted in that window, they can get it Bitcoin-timestamped, and then it looks like you. They can't touch your timeline before 4:39am or after 3:19pm. But that window is polluted.
So here's what's new in Inkan. When you revoke, you can now retroactively disavow that window. You do this on-chain. You basically say "Nothing signed by that signing key between 4:39am and 3:19pm speaks for me." A delegation-enabled client can then mark everything in that window as disavowed and can filter it out of your timeline. Impersonation gone.
One problem though. You yourself also posted in that window. Your real posts get disavowed along with the fake ones. Baby with bathwater.
That's the second new piece: re-ratification. You go through the disavowed window, pick out the events that are actually yours, and publish a re-ratification, also Bitcoin-timestamped. Those events come back and stay on your timeline, marked as re-ratified.
Net result: key stolen, key revoked, window disavowed, your own posts rehabilitated. The attacker's stuff is chased out, yours stays. Timeline repaired.
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Inkan
Inkan web client