Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
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Merrill Marshall Ahrens, MD

Individual provider Internal Medicine Physician · NPI 1194839225

Merrill Marshall Ahrens, MD is an Internal Medicine in Portland, Oregon. Graduated from Northwestern University Feinberg Medical School in 1989, 37 years ago. Practices with Legacy Clinics LLC, a 718-clinician group, accepts Medicare assignment and offers telehealth. Licensed in Oregon.

Years since qualifying
37
Trained at
Northwestern University Feinberg Medical School
Licensed in
OR
In the registry since
2006
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

19500 SE Stark St
Portland, OR 97233-5757
Phone: (503) 669-3900
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence ORMD17736 (OR)

Record details

NPI number1194839225
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorYes
NPI enumeratedAugust 18, 2006
Last updated in NPPESJuly 8, 2007

Medicare enrollment

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

Medicare specialtyINTERNAL MEDICINE
Medical schoolNORTHWESTERN UNIVERSITY FEINBERG MEDICAL SCHOOL
Graduated 1989 (37 years in practice)
Group practice Legacy Clinics Llc — 718 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations3 on file with Medicare

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