Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Dr. Mark D Fleming, MD

Individual provider Hematology (Pathology) Physician · NPI 1235148404

Dr. Mark D Fleming, MD practises Pathology in Boston, Massachusetts. Graduated from Harvard Medical School in 1993, 33 years ago. Practices with Children's Hospital Pathology Foundation Inc, a 15-clinician group and accepts Medicare assignment. Licensed in Massachusetts.

Years since qualifying
33
Trained at
Harvard Medical School
Licensed in
MA
In the registry since
2006
Specialties on file
2
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

300 Longwood Ave
Boston, MA 02115-5724 Not confirmed with CMS for 19 years — call before visiting
Phone: (617) 919-2664
Fax: (617) 730-0168
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Hematology (Pathology) Physician (primary) Taxonomy 207ZH0000X · Licence 153834 (MA)
Anatomic Pathology Physician Taxonomy 207ZP0101X · Licence 153834 (MA)

Record details

NPI number1235148404
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedAugust 6, 2006
Last updated in NPPESAugust 20, 2007

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyPATHOLOGY
Also practisesHEMATOLOGY
Medical schoolHARVARD MEDICAL SCHOOL
Graduated 1993 (33 years in practice)
Group practice Children'S Hospital Pathology Foundation Inc — 15 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Consulting Fee $20,250 5 payments
Food and Beverage $67 1 payment · a meal or drink at a meeting or visit, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Colleagues at Children's Hospital Pathology Foundation Inc

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 15 clinicians in the practice; 12 are shown here.

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