> For the complete documentation index, see [llms.txt](https://docs.kernel.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.kernel.ai/concepts/kern-id.md). # KERN ID {% embed url="" %} The Kernel Entity Reference Number (KERN) is a proprietary 10-digit ID that uniquely and persistently identifies a real-world entity. A KERN ID answers a simple question: **which entity does this CRM record actually mean?** It is not just a cleaned website, company name, or parent account. Kernel uses the available account evidence to decide the correct entity boundary, then assigns or reuses the KERN ID for that exact entity. Two records should share a KERN ID when they refer to the same entity at the same level. Two records should have different KERN IDs when they refer to different levels of the same family, such as a holding company, an operating subsidiary, a brand, or a physical branch.
Five inconsistent CRM records for the same company - entered as Google, GOOGLE, google, and the domain itself, with varied or missing websites - all resolve through Kernel to a single KERN ID: 9237577900, the operating company Google LLC in the United States. A different level, such as the parent Alphabet Inc., gets its own KERN ID.

The same company arrives in your CRM many ways; Kernel resolves every version to one persistent KERN ID. A different level - the parent Alphabet Inc., a brand, or a branch - gets its own.

## How Kernel decides the entity Before assigning a KERN ID, Kernel reviews the signals available on and around the CRM record, such as the company name, website, legal name, country, LinkedIn URL, address, related domains, parent relationship, and opportunity context. Kernel then uses [entity resolution](/concepts/entity-resolution.md) to resolve the record into a consistent identity: | Dimension | What it answers | Example | | ---------------------------------------- | ---------------------------------------------------- | ---------------------------------------------------------- | | Legal anchor | Which legal entity is responsible for this identity? | Kraft Heinz Company | | Country of incorporation or registration | Where is that legal entity registered? | US | | Trading identity | What name or website does the market recognize? | Jell-O | | Canonical website | What is the URL? | [kraftheinz.com/jell-o](https://www.kraftheinz.com/jell-o) | | Entity classification | What kind of entity is it? | Company / Business Unit | The KERN ID itself is just the persistent identifier. [Core entity data](/data/entity-data/core-entity-data.md) holds the fields that explain what the identifier represents. ## Legal and trading identities A legal entity is an incorporated or registered organization that can contract in its own name. Examples include **Google LLC**, **Salesforce, Inc.**, or **Kraft Heinz Company**. A trading identity is a real market-facing identity that operates through a legal entity. This can be a brand, division, business unit, academic unit, or physical establishment. These can receive their own KERN IDs when the CRM record clearly refers to them as the account being tracked. Examples: | CRM record means... | KERN ID represents... | Why | | ---------------------------------- | ------------------------ | ----------------------------------------------------------- | | Alphabet Inc. | Alphabet Inc. | The holding company itself | | Google | Google | The operating company or main operating brand, not Alphabet | | Jell-O | Jell-O | A brand/business unit under Kraft Heinz | | Lloyds Bank - London Bridge branch | The London Bridge branch | A specific establishment, not the whole bank | Hierarchy connects these entities together. It does not collapse them into one ID. A parent, subsidiary, brand, and branch can each have their own KERN ID when they represent distinct account identities. Entity type and role live in [Entity categories](/data/entity-data/entity-categories.md#categories-and-sub-categories), including company sub-categories such as Operating, HoldCo / Investment, Business unit, and Establishment. ## Reuse and persistence If Kernel has already seen the same entity, it reuses the existing KERN ID. If the record represents a new entity, Kernel creates a new KERN ID for that entity. The KERN ID should stay stable when superficial details change, such as punctuation, formatting, a redirected website, or a corrected company name. If the record is later found to refer to a different entity, it should be linked to that other entity's KERN ID instead. {% hint style="warning" %} **Limitations** Every KERN ID must ultimately be tied to a legal entity. Kernel can represent sub-legal entities such as brands, business units, branches, sites, hotels, plants, divisions, and academic units, but each is still connected to its closest responsible legal entity. Records with no credible organization or legal-entity association, such as a personal blog with only an individual's email address, would not receive a KERN ID. {% endhint %}