Slashing is a mechanism built into proof of stake blockchain protocol to discourage validators’ misbehavior such as persistent downtime, double signing and delegation. Punishments include reduction in stakes and suppression of future rewards and ejection.

Slashing is thus designed to incentivize node security, availability, and network participation. Ethereum 2.0, Celo, Cosmos, ICON and Polkadot have various slashing penalties for downtime, delegation and double signing.