What Is the Economic Cost to a Staker If They Participate in Signing a Block on a Rejected Fork?

The economic cost to a staker for signing a block on a rejected or malicious fork is the potential loss of their staked capital through a process called 'slashing'. Slashing is a punitive measure designed to deter dishonest behavior.

If the network determines the staker acted against the consensus, their locked-up funds can be partially or entirely confiscated, resulting in a direct financial loss.