Ralph Maximillian Koenker, M.D.

Primary specialty

Diagnostic Radiology PhysicianTaxonomy code 2085R0202X

License

G60981 Issued in CA

Practice address

250 Bon Air Rd
Greenbrae, CA 94904-1702

Phone

(415) 925-7000

NPI assigned

Jun 4, 2006

Sex

Male

Sole proprietor

No

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

Specialties & licenses 3

Addresses

Other identifiers 4

Medicare fee-for-service enrollment

Enrolled in CA

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 1

Specialty

Diagnostic RadiologyAlso: Interventional Radiology

Education

University of California, San Diego School of Medicine, 1985

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Group practices

Prima Medical FoundationGroup PAC ID 6406040138, 30 clinicians

California Advanced Imaging Medical Associates IncGroup PAC ID 0244144228, 85 clinicians

Practice addresses (Care Compare)

Hospital & facility affiliations

• Novato Community Hospital Hospital, Novato, CA, CCN 050131
• Marinhealth Medical Center Hospital, Greenbrae, CA, CCN 050360
• Sonoma Valley Hospital Hospital, Sonoma, CA, CCN 050090
• UCSF Medical Center Hospital, San Francisco, CA, CCN 050454
• Providence Queen of the Valley Medical Center Hospital, Napa, CA, CCN 050009

Merit-based Incentive Payment System (MIPS)

Final score

90.9 of 100Reported as group

Quality

91.91

Improvement activities

40

Cost

79.27

Merit-based Incentive Payment System (MIPS)

Final score

92.69 of 100Reported as group

Quality

96.63

Improvement activities

40

Cost

81.81

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Medicine

State licenses

Practice roles

Locations (25 of 30)

Interoperability endpoints

• Direct secure messaging: rkoenker194708@hisp.ehr.sutterhealth.org
• Direct secure messaging: rkoenker224830@direct-ucsfmedicalcenter.org

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.

• California Advanced Imaging Medical Associates Inc

  • Diagnostic Radiology Physician
  • San Francisco, CA
  • NPI 1881646909

  Neuroradiology

  Medicare reassignment Care Compare group NPD
• Prima Medical Foundation

  • Clinic/Center
  • Novato, CA
  • NPI 1811217946
  Medicare reassignment Care Compare group NPD
• Sutter Valley Medical Foundation

  • Multi-Specialty Clinic/Center
  • Modesto, CA
  • NPI 1669846986

  Diagnostic Radiology

  Medicare reassignment NPD
• Doctors Resources Company, LLC

  • Diagnostic Radiology Physician
  • Sacramento, CA
  • NPI 1659416907
  NPD
• Sutter Valley Medical Foundation

  • Durable Medical Equipment & Medical Supplies
  • Tracy, CA
  • NPI 1720930712
  NPD
• 1125 Sir Francis Drake Boulevard Operating Company, LLC

  • Long Term Care Hospital
  • Kentfield, CA
  • NPI 1760424261
  NPD (past)
• Marin General Hospital

  • General Acute Care Hospital
  • Greenbrae, CA
  • NPI 1396725677
  NPD (past)
• Prima Medical Group, Inc.

  • Family Medicine Physician
  • San Rafael, CA
  • NPI 1154377489
  NPD (past)
• Seton Medical Center

  • General Acute Care Hospital
  • Daly City, CA
  • NPI 1679608640
  NPD (past)
• Sonoma Valley Health Care District

  • General Acute Care Hospital
  • Sonoma, CA
  • NPI 1710063870
  NPD (past)
• Sutter Bay Hospitals

  • General Acute Care Hospital
  • Novato, CA
  • NPI 1104059153
  NPD (past)

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

• Marin General Hospital

  • General Acute Care Hospital
  • Greenbrae, CA
  • NPI 1396725677
  Care Compare affiliation
• Sonoma Valley Health Care District

  • General Acute Care Hospital
  • Sonoma, CA
  • NPI 1710063870
  Care Compare affiliation
• St. Joseph Health Northern California, LLC

  • General Acute Care Hospital
  • Napa, CA
  • NPI 1013080084
  Care Compare affiliation
• St. Joseph Health Northern California, LLC

  • General Acute Care Hospital
  • Napa, CA
  • NPI 1235218785
  Care Compare affiliation
• Sutter Bay Hospitals

  • General Acute Care Hospital
  • Novato, CA
  • NPI 1104059153
  Care Compare affiliation
• University of California, San Francisco

  • General Acute Care Hospital
  • San Francisco, CA
  • NPI 1689772592
  Care Compare affiliation

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

{
    "created_epoch": "1149379200000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1782604800000",
    "number": "1891734265",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "PO BOX 6102",
            "city": "NOVATO",
            "state": "CA",
            "postal_code": "949486102",
            "telephone_number": "415-884-3418",
            "fax_number": "415-883-8082"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "250 BON AIR RD",
            "city": "GREENBRAE",
            "state": "CA",
            "postal_code": "949041702",
            "telephone_number": "415-925-7000"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "180 Rowland Way",
            "address_purpose": "LOCATION",
            "city": "Novato",
            "state": "CA",
            "postal_code": "949455009",
            "country_code": "US",
            "telephone_number": "415-290-1500",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "last_name": "KOENKER",
        "first_name": "RALPH",
        "middle_name": "MAXIMILLIAN",
        "credential": "M.D.",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2006-06-04",
        "last_updated": "2026-06-28",
        "certification_date": "2026-06-28",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "2085N0700X",
            "taxonomy_group": "",
            "desc": "Radiology, Neuroradiology",
            "state": "CA",
            "license": "G60981",
            "primary": false
        },
        {
            "code": "2085R0202X",
            "taxonomy_group": "",
            "desc": "Radiology, Diagnostic Radiology",
            "state": "CA",
            "license": "G60981",
            "primary": true
        },
        {
            "code": "2085R0204X",
            "taxonomy_group": "",
            "desc": "Radiology, Vascular & Interventional Radiology",
            "state": "CA",
            "license": "G60981",
            "primary": false
        }
    ],
    "identifiers": [
        {
            "code": "05",
            "desc": "MEDICAID",
            "issuer": null,
            "identifier": "00G609810",
            "state": "CA"
        },
        {
            "code": "01",
            "desc": "Other (non-Medicare)",
            "issuer": "RAILROAD MEDICARE",
            "identifier": "300121787",
            "state": "CA"
        },
        {
            "code": "01",
            "desc": "Other (non-Medicare)",
            "issuer": "BLUE SHIELD",
            "identifier": "00G609810",
            "state": "CA"
        },
        {
            "code": "01",
            "desc": "Other (non-Medicare)",
            "issuer": "RAILROAD MEDICARE",
            "identifier": "300035771",
            "state": "CA"
        }
    ],
    "endpoints": [],
    "other_names": []
}

• Christina Leone Klein
• William Roland Klemme, M.D.
• Megan M Klenow, MD
• Stephanie April Kleven, ARNP, CNM
• Thomas R Knez, D.D.S.
• Michael Koffler, DMD
• Hannah Rowena Kopp-Yates, RN, CNM
• Meredith Kornfeld
• Makinley Marlene Kratina
• Frederick Joseph Kretzschmar, MD

• Diagnostic Radiology Physician in Greenbrae, CA
• Providers in Greenbrae, CA by specialty
• Diagnostic Radiology Physician in California

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Jun 28, 2026; 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.