How Does a 2/3 Majority PoS Signature Threshold Affect PoA Finality?

A 2/3 majority signature threshold in the PoS phase of PoA provides a high degree of finality. Once 2/3 of the total staked coins (or the validators representing them) have signed the block, the block is considered finalized and immutable under the protocol's rules.

This cryptographic commitment makes chain reorgs extremely difficult, as it would require 2/3 of the stake to collude and risk being slashed.

How Does the ‘Economic Finality’ of PoS Compare to the ‘Probabilistic Finality’ of PoW?
What Is the Theoretical Attack Vector Remaining in PoA?
How Is a 51% Attack Easier on a Proof-of-Work (PoW) Coin than a Proof-of-Stake (PoS) Coin?
What Is the Main Security Vulnerability Associated with a Small Set of PoA Validators?
What Is the Difference between a 51% Attack on a PoW versus a PoS Blockchain?
How Do Proof-of-Stake (PoS) Systems Achieve Economic Finality Differently than PoW Systems?
How Does Finality in Proof-of-Stake Systems Mitigate the Risk of a Deep Re-Org?
How Does the Finality Guarantee in PoS Compare to the Probabilistic Finality in PoW?

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