# Ownership (PECOS All Owners)

URL: https://docs.healthcare.dev/datasets/medicare-ownership

<Freshness dataset="medicare-ownership" />

|                 |                                                                                                                                                                                                                   |
| --------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Source          | CMS ([Hospital All Owners](https://data.cms.gov/provider-characteristics/hospitals-and-other-facilities/hospital-all-owners) and the SNF, FQHC, RHC, hospice and home health agency All Owners files, from PECOS) |
| Source id       | `cms-pecos-all-owners`                                                                                                                                                                                            |
| Release cadence | Quarterly (all six files together)                                                                                                                                                                                |
| License         | Public domain (US government work)                                                                                                                                                                                |
| Endpoint        | [`/v1/providers/{npi}/ownership`](/reference/providers/who-owns-the-facilities-an-npi-belongs-to)                                                                                                                 |
| MCP tool        | `get_provider_ownership`                                                                                                                                                                                          |
| Plans           | Pro and Team (`403` `plan-upgrade-required` below Pro)                                                                                                                                                            |

When a hospital, skilled nursing facility, federally qualified health center, rural health clinic,
hospice or home health agency enrolls in Medicare, it discloses who owns and controls it. CMS
publishes those disclosures quarterly: about 57,500 enrollments and 840,000 owner rows. Each
owner has a type (individual or organization), a role (a direct or indirect ownership interest,
operational or managerial control, an officer or director, a managing employee, a mortgage or
security interest, a partnership interest), the ownership percentage, the date it became
associated with the facility, and for organizations the business address and organization-type
flags, among them **private equity company** and **REIT**.

```sh
curl "https://api.healthcare.dev/v1/providers/1154392231/ownership?depth=2" \
  -H "Authorization: Bearer $HDEV_API_KEY"
```

```json
{
  "data": {
    "npi": "1154392231",
    "listed": true,
    "facilities_total": 1,
    "ownership_completeness": "Ownership is what each facility disclosed to CMS in its Medicare enrollment (PECOS All Owners files), as of the file's date. Public private equity and REIT data is known to be incomplete: ...",
    "derivation": "source_stated",
    "as_of": "2026-10-01",
    "facilities": [
      {
        "enrollment_id": "O20031010000033",
        "organization_name": "MAYO CLINIC ARIZONA",
        "facility_type": "hospital",
        "linked_by": "enrollment",
        "owners": [
          {
            "associate_id": "6507778255",
            "type": "organization",
            "name": { "display": "MAYO CLINIC" },
            "role": "OPERATIONAL/MANAGERIAL CONTROL",
            "role_kind": "operational_control",
            "percentage": 0,
            "association_date": "2010-01-01",
            "flags": { "private_equity": false, "reit": false, "non_profit": true },
            "owners_listed": true
          }
        ],
        "upstream": [
          {
            "associate_id": "6507778255",
            "organization_name": "MAYO CLINIC",
            "depth": 1,
            "path": ["7012829930", "6507778255"],
            "owners": ["..."]
          }
        ],
        "chain": { "depth_limit": 2, "truncated": false, "cycles": [] },
        "summary": { "owners": 19, "private_equity": false, "reit": false }
      }
    ]
  }
}
```

## How an NPI is linked

The All Owners files list enrollments, not NPIs. The NPI is linked through CMS's public
[Medicare enrollment](/datasets/medicare-enrollment) file: the organization enrollments that list
the NPI (as their NPI or one of their additional NPIs). When none of those has ownership
disclosures, the organization's other enrollments (same PECOS associate id) are used instead,
marked `linked_by: "associate_id"`; a group practice is linked to the hospital or hospice it runs
this way. One answer lists at most 20 facilities (`facilities_total` counts them all).

Individual NPIs (physicians, nurse practitioners) are not linked to the groups they bill through:
an individual's NPI answers `200` with `listed: false`. CMS's reassignment file would make that
link; it isn't loaded yet.

## Chains

Where an owner is itself an organization with its own disclosures (the same PECOS associate id
appears as a facility in the files), `owners_listed` is true and its owners are in `upstream`,
nearest first, up to `depth` levels (default 3, at most 5; `0` for the facility's own owners
only). Each organization appears once, at the depth the chain first reached it, with the `path`
of associate ids that led there. When an owner leads back to an organization already on the chain
(a facility owned by its own hospital, which lists the facility in turn, or an organization that
lists itself), the chain stops there and `chain.cycles` names it. `chain.truncated` says that an
owner at the depth limit lists owners of its own.

Percentages are what each facility disclosed for each owner, never multiplied along the chain:
CMS already lists indirect owners with their indirect share. Officers, directors and managing
employees are usually listed with `0` or no percentage.

## What public ownership data leaves out

Show `ownership_completeness` with every answer. The flags are organization types the facility
reported about its owners; owners below 5% and investors behind holding companies may not be
listed, and private equity firms often own through holding companies that don't check the
private equity box. A `false` or `null` flag, or `summary.private_equity: false`, means none was
disclosed, never that there is no private equity or REIT owner. `derivation: "source_stated"`:
the owners, roles, shares and flags are as disclosed; we add nothing to them, and the chain only
follows the associate ids CMS lists.

## Limits

Ownership is a derived lookup: each account (all its keys together) can look up a limited number
of different NPIs a day ([daily lookup limits](/rate-limits#daily-lookup-limits-on-derived-data));
repeats don't count. Owners of equal role and share come in an order that is stable for your
account.

## Possible exclusion matches

The same feature covers entity matching for OIG exclusions: most records in the
[OIG exclusions list](/datasets/oig-exclusions) carry no NPI. We match those to NPIs by rules, and
the [joined provider answer](/joined-answers#providers) lists the results as
`exclusion_matches`: possible matches, derived, never a finding that a provider is excluded.

- A candidate needs the **same name** (last and first name, or business name, once case, spacing,
  punctuation and legal-form words like "Inc" are set aside) in the **same state**, from NPPES or
  CMS's enrollment file. Date of birth is never used: we don't store it.
- A **different middle name** means another person, and a **specialty that can't be the same
  profession** (an aide and a surgeon) rules a candidate out.
- What else agrees raises `confidence`: middle name, the same street address or ZIP code, a
  specialty that fits. `evidence` says field by field what matched, and `candidates` how many
  providers matched the record.
- One candidate with strong evidence is published as `derivation: "derived"`. Several candidates,
  or one with weaker evidence, are checked by a person first and only then shown, as
  `derivation: "reviewed"`. Name and state alone are never shown.

Confirm any possible match with OIG's online search (exclusions.oig.hhs.gov), which verifies SSN
or EIN. `exclusion_recorded` and `matched_by: "npi_as_listed"` keep meaning what they always did.
