NPPES file of Aug 9, 2026

Mark Janssen, MD

Anatomic Pathology & Clinical Pathology Physician · Anaheim, CA

Mark Janssen, MD is an anatomic pathology & clinical pathology physician with a practice address in Anaheim, California, and NPI 1407923345, issued on Nov 29, 2006. Check the license (California A24214, as entered in NPPES) on the Medical Board of California; the federal record below is the public data PlainDoctor holds for this provider.

Record from CMS NPPES, file of Aug 9, 2026 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1407923345
Name
Mark Janssen
Credential
MD
Primary taxonomy
Anatomic Pathology & Clinical Pathology Physician 207ZP0102X
License number
A24214 CA
Self-reported in NPPES; status is on the state search
Practice location
441 N Lakeview Ave, Anaheim, CA 92807
Phone
(888) 988-2800
Enumerated
Nov 29, 2006
Record last updated
Sep 23, 2008 (not updated in 18 years: call before relying on the address or phone)
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). A record is not a license: verify it with the state board.
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8 nearest anatomic pathology & clinical pathology physician records → All 1,554 in California → Look up another NPI →

Also registered at 441 N Lakeview Ave

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Adan Abarca, MDFamily Medicine Physician1760553689
  2. Peter Abdel Sayed, MDVascular & Interventional Radiology Physician1760553648
  3. Behnam Abdollahi, MDDermatopathology Physician1598836520
  4. Mark Abramson, MDInternal Medicine Physician1396812202
  5. Suzanne Ackley, MDNeuromusculoskeletal Medicine & OMM Physician1740351667
  6. Carol Ahmed, D.O.Family Medicine Physician1598962961

Verify Mark Janssen in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of California
    Search for license A24214    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Open the California license search

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Mark Janssen among 1,554 anatomic pathology & clinical pathology physician records in California

Mark Janssen, MD is one of 1,554 anatomic pathology & clinical pathology physician records with a practice address in California. 65% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does not. Its NPI, issued in 2006, is newer than 7% of them.

  • NPI issued2006 · 7% of these records are older, 57% newer
  • In a Medicare fileNo · 65% of these records are
  • In the CMS Doctors and Clinicians fileNo · 57% of these records are
  • Record last updated2008 · 61% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207ZP0102X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

Anatomic Pathology & Clinical Pathology Physician providers in California

There are 1,554 anatomic pathology & clinical pathology physician records in California. No Medicare prescribing, quality score, industry payment or hospital affiliation is published for this NPI.

All 1,554 in California → Every provider in Anaheim → Anatomic Pathology & Clinical Pathology Physician nationwide →

The 8 anatomic pathology & clinical pathology physician records with the nearest ZIP codes

  1. David Huebner-Chan, MDAnaheim, CA 928071134290190
  2. Greg Marganian, MDAnaheim, CA 928071558561134
  3. Jana Pindur, MDAnaheim, CA 928071003983008
  4. Asma Quddusi, MDAnaheim, CA 928071477612133
  5. Visesh RavikumarAnaheim, CA 928071053949206
  6. Stephen Koh, M.D., PH.D.Anaheim, CA 928061003057316
  7. Jason Scapa, M.D.Anaheim, CA 928061982099230
  8. Ali Ali, M.D.Anaheim, CA 928041598786113

Common questions

What is Mark Janssen, MD's NPI number?

Mark Janssen, MD's National Provider Identifier (NPI) is 1407923345, issued on Nov 29, 2006. An NPI identifies a provider in billing; it is not a license.

Where is Mark Janssen, MD located?

The NPPES record lists a practice address at 441 N Lakeview Ave, Anaheim, CA, 92807. Phone: (888) 988-2800. Providers update this record themselves, so call before visiting.

How can I verify Mark Janssen, MD's license?

NPPES lists California license number A24214, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. An NPI identifies who bills; it is not a license.

Written with AI tools from the named public files; every figure is computed from those files (how it is made).

Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.