{
  "v": 1,
  "requestId": "70b29f11-52d8-4c06-b547-5c2383a6f97b",
  "chainId": 1,
  "window": {
    "toBlock": 26049165,
    "fromBlock": 26048866,
    "toBlockHash": "0x20426a3e4b845b87cd43d6683e11e5637765c8319cd7126a02222ae16a8c65cd"
  },
  "answerType": "uint256",
  "answer": "12965000",
  "figure": "12965000",
  "definitions": {
    "answer": "the block number, as a number",
    "source": "Answer from a reputable public source you actually read (ethereum.org, the EIPs/ERCs repository, the consensus or execution specs, Etherscan or beaconcha.in, or a major news archive) and name it.",
    "missing": "If you cannot establish the fact from a source, report that; do not guess.",
    "subject": "The question is about Ethereum's protocol and history. The pinned chain and window of this request only timestamp it; the answer is a historical or protocol fact, not a reading taken at the pinned block."
  },
  "recipe": {
    "kind": "panel",
    "source": "https://ethereum.org/ethereum-forks/"
  },
  "notes": "Ethereum.org's 'Timeline of all Ethereum forks' lists the London block number as 12,965,000 and identifies EIP-1559 as part of the London upgrade. This is a historical fact as specified by the brief; the pinned window timestamps the request and is not a range to scan."
}