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  "id": "ethereum-slashing",
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  "collection": "ethereum",
  "title": "Ethereum slashing: conflicting signatures, penalties and downtime",
  "description": "Separate slashable validator messages from routine downtime, with a duplicated-key example and an explanation of correlated penalties and exits.",
  "aliases": [
    "validator slashing",
    "Ethereum penalties",
    "double signing"
  ],
  "dates": {
    "published": "2026-10-02",
    "modified": "2026-10-02",
    "verified": "2026-10-02T15:10:23.134Z",
    "dataAsOf": "2026-10-02"
  },
  "authorship": {
    "publisher": "Degrees of Satoshi editorial project",
    "process": "AI-assisted research and drafting with a separate automated source-verification pass; no external expert or named human review is implied."
  },
  "quickAnswer": {
    "text": "Slashing penalizes specific conflicting validator actions, including double proposals, double votes and surround votes. It is different from ordinary missed-duty penalties. A slashed validator is forced to exit and can lose stake, with losses affected by correlated slashing. Accidental duplicated signing setups can produce slashable messages.",
    "claimId": "ethereum-slashing-quick-answer",
    "sourceIds": [
      "penalties",
      "gasper",
      "staking"
    ]
  },
  "keyFacts": [
    {
      "label": "Slashable behavior",
      "value": "Specific conflicting proposals or attestations",
      "sourceIds": [
        "penalties"
      ],
      "id": "slashable-behavior",
      "claimId": "ethereum-slashing-fact-slashable-behavior"
    },
    {
      "label": "Ordinary absence",
      "value": "Missed rewards and penalties are distinct from slashing",
      "sourceIds": [
        "penalties"
      ],
      "id": "ordinary-absence",
      "claimId": "ethereum-slashing-fact-ordinary-absence"
    },
    {
      "label": "Correlation",
      "value": "Losses can increase when many validators are slashed together",
      "sourceIds": [
        "penalties"
      ],
      "id": "correlation",
      "claimId": "ethereum-slashing-fact-correlation"
    }
  ],
  "prerequisites": [
    "ethereum-proof-of-stake-finality",
    "ethereum-staking-withdrawals"
  ],
  "sections": [
    {
      "id": "conflicting-messages",
      "heading": "The protocol evaluates signed messages, not a person’s intention",
      "sourceIds": [
        "penalties",
        "gasper"
      ],
      "paragraphs": [
        "Slashable conditions concern contradictions in what a validator signs. Examples include proposing two different blocks for one slot, double-voting at the same target epoch or making a vote that surrounds another in the forbidden pattern.",
        "The protocol can evaluate the messages without knowing why they were produced. Malice is one possibility, but operational mistakes can also create conflicting signatures."
      ]
    },
    {
      "id": "duplicate-example",
      "heading": "Example: a backup must not become a second active signer",
      "sourceIds": [
        "staking",
        "penalties"
      ],
      "paragraphs": [
        "Imagine two machines both actively using the same validator key. If they follow different views of a slot and sign incompatible proposals or attestations, the resulting evidence can satisfy a slashing condition.",
        "This is why redundancy is not simply copying keys and turning everything on. The relevant operational objective is continuity without contradictory signing; ordinary website-style failover assumptions do not establish that property."
      ]
    },
    {
      "id": "penalty-stages",
      "heading": "Initial loss and correlated loss are different parts of the result",
      "sourceIds": [
        "penalties",
        "eip7251"
      ],
      "paragraphs": [
        "A slashing event forces an exit and applies penalties. The eventual amount depends on applicable protocol parameters and on other slashings around the event, rather than a universal fixed percentage quoted without context.",
        "Correlated penalties make widespread conflicting behavior more costly. Older documentation can contain numeric examples from earlier upgrades; this entry deliberately avoids presenting those amounts as today’s calculator."
      ]
    },
    {
      "id": "downtime",
      "heading": "Being offline is harmful without automatically being slashable",
      "sourceIds": [
        "penalties",
        "pos"
      ],
      "paragraphs": [
        "A validator that misses normal duties can lose rewards and incur ordinary penalties. That is not identical to producing evidence of conflicting votes. Describing every connection outage as slashing blurs an important distinction.",
        "During prolonged nonfinality, inactivity-leak penalties can become significant. The statement that routine absence is not itself a slashable offense is therefore not a promise that extended absence is cheap."
      ]
    }
  ],
  "faq": [
    {
      "question": "Will a short internet outage automatically slash a validator?",
      "answer": "Missing duties is not itself the same as the specific conflicting-signature conditions for slashing, although missed rewards and other penalties can apply.",
      "sourceIds": [
        "penalties"
      ]
    },
    {
      "question": "Can a validator be slashed accidentally?",
      "answer": "Yes. Operational errors such as conflicting signing with the same key can produce slashable evidence regardless of intent.",
      "sourceIds": [
        "staking",
        "penalties"
      ]
    },
    {
      "question": "Is the loss always a fixed amount?",
      "answer": "No. Protocol parameters, validator balance and correlated slashings affect the result. Historical examples should not be reused as a current universal amount.",
      "sourceIds": [
        "penalties",
        "eip7251"
      ]
    }
  ],
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      "statement": "Slashing penalizes specific conflicting validator actions, including double proposals, double votes and surround votes. It is different from ordinary missed-duty penalties. A slashed validator is forced to exit and can lose stake, with losses affected by correlated slashing. Accidental duplicated signing setups can produce slashable messages.",
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          "Read proposal/double/surround conditions and forced exit, ordinary missed-duty distinction. Avoids stale numeric slash examples in docs."
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    "articles": [
      "ethereum-staking-withdrawals",
      "ethereum-proof-of-stake-finality",
      "ethereum-nodes-rpc",
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  "revisionHistory": [
    {
      "date": "2026-10-02",
      "kind": "published",
      "summary": "First publication after primary-source research and independent automated verification."
    }
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  "citation": "Degrees of Satoshi editorial project. “Ethereum slashing: conflicting signatures, penalties and downtime.” Published 2026-10-02; updated 2026-10-02. https://degreesofsatoshi.com/encyclopedia/ethereum-slashing/"
}