Stem Operating LLC

Primary specialty

Neurological Surgery PhysicianTaxonomy code 207T00000X

Legal business name

STEM OPERATING LLC

Practice address

501 S Cherry St Ste 1100
Denver, CO 80246-1323

Phone

(800) 975-1652

NPI assigned

Jul 25, 2022

Organization subpart

No

Registry information is reported by the provider to CMS and is not verified. About this source

Authorized official

Name

Dr. Alexander Mason, MDNPI 1275758039

Title

Ceo

Phone

(404) 227-4864

Specialties & licenses 1

Addresses

Locations

Practitioners 2

Individual providers connected to this organization through Medicare benefit reassignment, Care Compare group membership or National Provider Directory roles.

• Alexander Michael Mason, MD

  • Neurological Surgery Physician
  • Saint Paul, MN
  • NPI 1275758039
  NPD (past) Authorized official
• Eugene Edward Galperin, MD

  • Nephrology Physician
  • St George, UT
  • NPI 1548318330
  NPD

The complete NPPES record for this NPI in the NPI Registry API format.

{
    "created_epoch": "1658707200000",
    "enumeration_type": "NPI-2",
    "last_updated_epoch": "1741564800000",
    "number": "1316673171",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "501 S CHERRY ST STE 1100",
            "city": "DENVER",
            "state": "CO",
            "postal_code": "802461323"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "501 S CHERRY ST STE 1100",
            "city": "DENVER",
            "state": "CO",
            "postal_code": "802461323",
            "telephone_number": "800-975-1652"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "organization_name": "STEM OPERATING LLC",
        "organizational_subpart": "NO",
        "enumeration_date": "2022-07-25",
        "last_updated": "2025-03-10",
        "certification_date": "2025-03-10",
        "status": "A",
        "authorized_official_last_name": "MASON",
        "authorized_official_first_name": "ALEXANDER",
        "authorized_official_title_or_position": "CEO",
        "authorized_official_telephone_number": "404-227-4864",
        "authorized_official_name_prefix": "Dr.",
        "authorized_official_credential": "MD"
    },
    "taxonomies": [
        {
            "code": "207T00000X",
            "taxonomy_group": "193200000X MULTI-SPECIALTY GROUP",
            "desc": "Neurological Surgery",
            "state": null,
            "license": null,
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Stem Medical Group New Jersey PC
• Stem Medical Group North Carolina, PC
• Stem Medical Group Oregon PC
• Stem Medical Group Puerto Rico PC
• Stem Medical Group, PC
• Jerra N. Stemmle
• Stems Therapy Collective PLLC
• Lauren Stenftennagel
• Sandra H Stenmark, M.D.
• John Christian Stennes

• Neurological Surgery Physician in Denver, CO
• Providers in Denver, CO by specialty
• Neurological Surgery Physician in Colorado

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Mar 10, 2025; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.