NPPES file of Aug 9, 2026

Mark J. Marshall, D.O.

Internal Medicine Physician · Sharon, CT

Mark J. Marshall, D.O. is an internal medicine physician with a practice address in Sharon, Connecticut, and NPI 1326197963, issued on Jan 10, 2007. Check the license (Connecticut 000529, as entered in NPPES) on the Connecticut Medical Examining Board; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · Medicare files 2023 and 2024 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1326197963
Name
Mark J. Marshall
Credential
D.O.
Primary taxonomy
Internal Medicine Physician 207R00000X
License numbers
000529 CT
203678 NY
Self-reported in NPPES; status is on the state search
Practice location
50 Hospital Hill RD, Sharon, CT 06069
Phone
(860) 364-4201
Enumerated
Jan 10, 2007
Record last updated
Jul 8, 2007 (not updated in 19 years: call before relying on the address or phone)
Fax
(860) 364-4211
Medicare enrollment
Enrolled (PECOS I20150720002531); accepts Medicare assignment
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
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Also registered at 50 Hospital Hill RD

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

  1. Lois Alimonti, NPFamily Nurse Practitioner1205040219
  2. Jessica Bannerman, OTR/LOccupational Therapist1851858559
  3. Alexis Bell, DOEmergency Medicine Physician1730715665
  4. Md Bhuiyan, DOInternal Medicine Physician1871053413
  5. Joseph Catania, M.DSurgery Physician1093710477
  6. Birgit Clague, AGACNP-BCAcute Care Nurse Practitioner1043936578

Verify Mark J. Marshall in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersConnecticut Medical Examining Board
    Search for license 000529
    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 Connecticut license search

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97% fewer Medicare Part D claims than the average internal medicine physician in 2024

108 Medicare Part D claims for 45 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 11% of claims.

  1. Mark Marshall108
  2. Specialty average3,176

Most prescribed

  1. Prednisone11 claims

Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.

The MIPS final score for 2023 (Medicare payment program): 94.2 of 100

The Merit-based Incentive Payment System score is reported for this clinician. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.

  1. Qualityout of 100 · 30% of the final score78.3
  2. Costnot scored (reweighted)
  3. Promoting interoperabilityout of 100 · 25%100.0
  4. Improvement activities40 of 40 points · 15%100.0

Source: CMS Quality Payment Program, MIPS performance year 2023; category weights for 2023 (qpp.cms.gov).

Bills Medicare through one group practice

  1. Nuvance Health Medical Practice PCSharon, CT

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

5 internal medicine physician records list a practice address in Sharon

They are 5 of the 85 NPPES records with a practice address in Sharon, and 2,623 internal medicine physician records in Connecticut.

Other internal medicine physician records in Connecticut

  1. Hoda Abdel Salam, M.D.New Britain, CT1144509316
  2. Gada Abdelhafiz, MDNew London, CT1467649558
  3. Racha Abi Melhem, MDDerby, CT1902471352
  4. Gerard Abidor, D.O.Bridgeport, CT1518014539
  5. Lilyan AbrahamFarmington, CT1447693254
  6. Richard Abraham, M.D.Canton, CT1023044252
  7. Odaliz Abreu-Lanfranco, MDNew Haven, CT1538276134
  8. Kenneth Abriola, MDGlastonbury, CT1083693022
  9. Florentino Abueg, MDSouthbury, CT1649372558
  10. Nila Aburto, MDStamford, CT1396325718

Common questions

What is Mark J. Marshall, D.O.'s NPI number?

Mark J. Marshall, D.O.'s National Provider Identifier (NPI) is 1326197963, issued on Jan 10, 2007. An NPI identifies a provider in billing; it is not a license.

Where is Mark J. Marshall, D.O. located?

The NPPES record lists a practice address at 50 Hospital Hill RD, Sharon, CT, 06069. Phone: (860) 364-4201. Providers update this record themselves, so call before visiting.

How can I verify Mark J. Marshall, D.O.'s license?

NPPES lists Connecticut license number 000529, as entered by the provider. Search the Connecticut Medical Examining Board at https://www.elicense.ct.gov/Lookup/LicenseLookup.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

How much does Mark J. Marshall, D.O. prescribe under Medicare Part D?

In 2024, Mark J. Marshall, D.O. had 108 Medicare Part D claims for 45 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.

What is Mark J. Marshall, D.O.'s MIPS final score?

The 2023 MIPS final score is 94.2 of 100. The average among 454,083 clinicians with a measured score was 83.5.

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

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.