--- title: "Over-merge" summary: "An over-merge is a cluster containing records from more than one real entity — the failure that turns two customers, two suppliers or two counterparties into one." canonical_url: https://entitybind.com/glossary/over-merge last_updated: 2026-10-15 copy: full --- # Over-merge > An over-merge is a cluster containing records from more than one real entity — the failure that turns two customers, two suppliers or two counterparties into one. Canonical page: https://entitybind.com/glossary/over-merge Last updated: 2026-10-15 Glossary · Measurement ## How to read this The definition as the field writes it comes first, weaknesses and all. What Entity Bind does about it comes last, in its own paragraph, so you can take one without the other. [Filed under measurement](https://entitybind.com/glossary#measurement). By [James Rooney](https://entitybind.com/about), founder of Entity Bind · Last revised 15 October 2026 ## What over-merge means Over-merging is the cluster-level form of a false positive, and it is worse than the sum of the bad decisions that caused it. One wrong edge between two clean ten-record clusters yields a twenty-record cluster in which every record now has ten wrong neighbours, and the golden record assembled from it mixes two companies' addresses, numbers and ownership. The classic causes are structural rather than accidental: a common name matched without rarity weighting, a shared registered office at a formation agent, a group whose subsidiaries all carry the parent's name, and transitive chaining through a hub record that resembles everything. It is also the failure that is hardest to undo. Once a merged identifier has been distributed to downstream systems, splitting it requires knowing which facts belonged to which side, and most systems did not keep that. This is the practical argument for storing decisions rather than only outcomes: a merge you can explain is a merge you can reverse. Entity Bind guards against it in three places — rarity weighting so a common token cannot carry a decision, a contradiction guard that blocks transitive merges across conflicting strong identifiers, and the confidence floor below which no binding is representable — and it records every merge as a reversible decision with a receipt. An attributed record detaches into a fresh entity; ambiguous legacy facts and general multi-member splits fail closed rather than guessing. ## Where this shows up in Entity Bind Three pages where this term stops being vocabulary and starts changing an answer, a payload or a price. - [Precision, recall and abstention](https://entitybind.com/guides/precision-recall-and-abstention): The precision-recall trade-off is usually described as a two-way choice, and in entity resolution that description is wrong. There is a third output — declining… - [CRM and RevOps](https://entitybind.com/use-cases/crm-and-revops): The duplicate-account problem in a running CRM, and what a merge that should not have happened costs to unwind. - [The accuracy method](https://entitybind.com/accuracy): Every published rate with the population it was measured over, its interval and its fixture — including the input shapes that fail. The fastest way past a definition is a file: which of your rows are the same company, which of your existing matches we would not have made, and what we could not decide. [Start free →](https://app.entitybind.com/app?signup=1) ## The terms next to this one Each with its own sentence, because the next question is usually about the word beside this one. - [Fragmentation](https://entitybind.com/glossary/fragmentation): Fragmentation is the opposite failure to over-merging: one real entity split across several clusters, so the same company is counted, contracted with or invoiced more than once. - [False bind](https://entitybind.com/glossary/false-bind): A false bind is Entity Bind's name for the error it treats as unacceptable: a record attached to the wrong company entity and returned as a decided match. - [Cluster](https://entitybind.com/glossary/cluster): A cluster is the set of records a resolver has decided belong to one entity, and the object that cluster-level metrics are scored against. - [B-cubed (B³)](https://entitybind.com/glossary/b-cubed): B-cubed is a cluster-level evaluation metric that scores precision and recall from the point of view of each individual record, asking what share of its assigned cluster genuinely belongs with it and what share of its true family it was placed with. - [Decision receipt](https://entitybind.com/glossary/decision-receipt): A decision receipt is the durable, retrievable record of why a particular match was made — the features, the probability, the thresholds in force, the sources cited and the version of the pipeline that decided — addressable by an identifier returned with the answer. - [u-probability](https://entitybind.com/glossary/u-probability): The u-probability of a comparison field is the probability that the field agrees by chance given that the pair is not a match — a measure of how common a value is, and therefore of how little an agreement proves. ### Answered at length elsewhere - [Survivorship and golden records](https://entitybind.com/guides/survivorship-and-golden-records) (Guide): Merging records is only half the job. Field-level survivorship, source precedence, temporal facts, per-field provenance, and why last-confirmed beats first-seen. ## The other 13 terms on this shelf How you tell whether any of it worked, and which numbers may not be quoted without which other numbers. - [Precision](https://entitybind.com/glossary/precision) - [Recall](https://entitybind.com/glossary/recall) - [F1 score](https://entitybind.com/glossary/f1) - [B-cubed (B³)](https://entitybind.com/glossary/b-cubed) - [Pairwise metrics](https://entitybind.com/glossary/pairwise-metrics) - [Cluster metrics](https://entitybind.com/glossary/cluster-metrics) - [Recall@k](https://entitybind.com/glossary/recall-at-k) - [Calibration](https://entitybind.com/glossary/calibration) - [Expected calibration error (ECE)](https://entitybind.com/glossary/expected-calibration-error) - [Wilson interval](https://entitybind.com/glossary/wilson-interval) - [False positive](https://entitybind.com/glossary/false-positive) - [False bind](https://entitybind.com/glossary/false-bind) - [Fragmentation](https://entitybind.com/glossary/fragmentation) Previous, alphabetically: [Normalisation](https://entitybind.com/glossary/normalisation) · Next, alphabetically: [Pairwise metrics](https://entitybind.com/glossary/pairwise-metrics) ## Evidence basis Internal fixtures only. The historical 2026-08-29 per-tier recording covers 317 GB companies with identifier-rich arrivals seeding the catalogue first; the context tier includes country and registered-town prose. Its legacy replay has no full-prompt-verified calls and cannot certify current calibration. The September 5 CI reports cover 1,176 labelled pairs and 705 records over 250 companies using offline stubs. These are not independent customer holdouts or live production validation; the 99% minimum-input product target remains unmet. Scope is company and organisation identity only — not people, vessels, bank-account ownership, sanctions or emissions. Results may not be used for eligibility decisions about individuals, including employment, credit and tenancy. ## Start with your own company records. Create your workspace, verify your email and run your first company file. The Free plan needs no card. Create API keys in your workspace when you need an integration. [Start free](https://app.entitybind.com/app?signup=1) · [All 64 terms](https://entitybind.com/glossary) 300 credits. No card. For a guided review of your file, explore [the Merge Safety Sprint](https://entitybind.com/audit-pack). --- Entity Bind resolves companies and organisations only. It does not resolve people, vessels, bank-account ownership, sanctions exposure, emissions or geolocation, and its results may not be used for eligibility decisions about individuals, including employment, credit and tenancy. This is the Markdown copy of https://entitybind.com/glossary/over-merge, assembled from the same data the page renders and carrying every sentence, table row, figure and question the page's main content carries. The HTML page is canonical; it adds the layout, the navigation and the interactive parts (the ask panel, the forms), which a copy can name but not run. Every page on the site, with a line on each: https://entitybind.com/llms.txt.