Runs of statements that recur (after rename canonicalisation) in multiple files. Likely copy-paste — extract a shared helper. Canonicalisation maps identifier tokens to per-window local indices so renamed copies still match. Minimum window is 6 consecutive statements (and 80 characters) to keep noise low. Cross-file: per-file run writes fingerprints into the shared corpus; finalize groups by hash and emits one Issue per duplicate set with related spans pointing at every other occurrence.

// src/orders.ts:42
const items = parseItems(input);
const validated = validateItems(items);
const priced = priceItems(validated, currency);
const taxed = applyTax(priced, region);
const total = sumItems(taxed);
return { items: taxed, total };

// src/quotes.ts:88 — same shape, renamed: flagged as related
const products = parseItems(input);
const checkedProducts = validateItems(products);
const pricedProducts = priceItems(checkedProducts, currency);
const taxedProducts = applyTax(pricedProducts, region);
const total = sumItems(taxedProducts);
return { items: taxedProducts, total };

// fix: extract once
export function pipeline(input: RawInput, currency: Currency, region: Region) {
  const items = parseItems(input);
  const validated = validateItems(items);
  const priced = priceItems(validated, currency);
  const taxed = applyTax(priced, region);
  return { items: taxed, total: sumItems(taxed) };
}

Suppressing: each duplicate group is emitted as a single Issue covering every occurrence — one primary location plus related spans for the rest. A cofferdam-ignore: Refactor.DuplicateBlock comment placed at any occurrence (the primary one or any related one) suppresses the whole finding, not just that copy. You don't need to find and suppress every occurrence individually — one ignore comment on either side of a duplicated pair is enough.