John Nicholas Harker, DO

Primary specialty

Orthopaedic Surgery PhysicianTaxonomy code 207X00000X

License

OS-0006819 Issued in FL

Practice address

12955 Seminole Blvd
Largo, FL 33778-2399

Phone

(727) 586-4752

NPI assigned

Aug 30, 2006

Sex

Male

Sole proprietor

Yes

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

Specialties & licenses 2

Addresses

Medicare fee-for-service enrollment

Enrolled in FL, CA2 enrollments

Eligible to order & refer

• Part B services: Yes
• Medical equipment: Yes
• Home health: Yes
• Power mobility devices: Yes
• Hospice: Yes

Green means eligible to order or refer.

Enrollment records 2

Specialty

Orthopedic Surgery

Education

Nova Southeastern College of Osteo Medicine, 1989

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Group practices

Paul J Wisniewski DO IncGroup PAC ID 5092240606, 19 clinicians

Practice addresses (Care Compare)

Hospital & facility affiliations

• Enhabit Home Health Home health agency, Clearwater, FL, CCN 109687
• Providence St Mary Medical Center Hospital, Apple Valley, CA, CCN 050300
• HCA Florida Largo Hospital Hospital, Largo, FL, CCN 100248

Procedures performed for Medicare patients

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Osteopathy

State licenses

Practice roles

Locations

Networks

• Optimum HealthCare HMO Network
• Freedom Health HMO Network
• BSC 65 PLUS INDIVIDUAL MAPD

Organizations this provider is connected to: Medicare benefit reassignments (the organization bills Medicare for this provider’s services), Care Compare group memberships and National Provider Directory roles.

• Clearwater Orthopedic & Sports Medicine Inc

  • Orthopaedic Surgery Physician
  • Clearwater, FL
  • NPI 1306041421
  Medicare reassignment NPD Authorized official
• Paul J Wisniewski DO Inc

  • Trauma Surgery Physician
  • Apple Valley, CA
  • NPI 1780433698
  Medicare reassignment Care Compare group NPD

Hospitals and other facilities this clinician is affiliated with according to Medicare Care Compare.

• Eh Home Health of the Southeast, LLC

  • Home Health Agency
  • Clearwater, FL
  • NPI 1134535545
  Care Compare affiliation
• Largo Medical Center, Inc.

  • General Acute Care Hospital
  • Largo, FL
  • NPI 1144274879
  Care Compare affiliation
• St. Mary Medical Center

  • Advanced Practice Midwife
  • Apple Valley, CA
  • NPI 1043406440

  Hospital

  Care Compare affiliation
• St. Mary Medical Center

  • General Acute Care Hospital
  • Apple Valley, CA
  • NPI 1669456299
  Care Compare affiliation
• St. Mary Medical Center

  • General Acute Care Hospital
  • Apple Valley, CA
  • NPI 1710109186
  Care Compare affiliation

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

{
    "created_epoch": "1156896000000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1757635200000",
    "number": "1013026269",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "12955 SEMINOLE BLVD",
            "city": "LARGO",
            "state": "FL",
            "postal_code": "337782399",
            "telephone_number": "727-586-4752"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "12955 SEMINOLE BLVD",
            "city": "LARGO",
            "state": "FL",
            "postal_code": "337782399",
            "telephone_number": "727-586-4752"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "18523 Corwin Rd Ste A",
            "address_purpose": "LOCATION",
            "city": "Apple Valley",
            "state": "CA",
            "postal_code": "923072300",
            "country_code": "US",
            "telephone_number": "909-712-2764",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "last_name": "HARKER",
        "first_name": "JOHN",
        "middle_name": "NICHOLAS",
        "name_prefix": "Dr.",
        "credential": "DO",
        "sole_proprietor": "YES",
        "sex": "M",
        "enumeration_date": "2006-08-30",
        "last_updated": "2025-09-12",
        "certification_date": "2025-09-12",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "207X00000X",
            "taxonomy_group": "",
            "desc": "Orthopaedic Surgery",
            "state": "CA",
            "license": "20A23999",
            "primary": false
        },
        {
            "code": "207X00000X",
            "taxonomy_group": "",
            "desc": "Orthopaedic Surgery",
            "state": "FL",
            "license": "OS-0006819",
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Patricia Hanratty
• Claire Haraminac
• Kimberly Ann Harden, MAAT, ATR, RMHCI
• Emilia Harding
• John A Hardy
• Harkins Dental Associates
• Samantha Leanna Harlow, PMHNP-BC
• Scott Harlow
• Harmony Wellness Care LLC
• Kingston Harness

• Orthopaedic Surgery Physician in Largo, FL
• Providers in Largo, FL by specialty
• Orthopaedic Surgery Physician in Florida

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Sep 12, 2025; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• Medicare enrollment (CMS PECOS): enrollments, PAC IDs and benefit reassignments; Order and Referring.
• Medicare Care Compare (CMS): clinician profile, group practices, facility affiliations, MIPS scores and star ratings.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.