Mark T. Fahlen, MD, Inc. a Professional Medical Corporation
NPI 1659537264 · Nephrology Physician · Modesto, CA
Enrolled with Medicare as Part B Supplier - Clinic/Group Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark T. Fahlen, MD, Inc. a Professional Medical Corporation is a Nephrology Physician organization in Modesto, CA (NPI 1659537264).
Provider details
- NPI number
- 1659537264
- Entity type
- Organization
- Primary specialty
- Nephrology PhysicianAllopathic & Osteopathic Physicians
- Organization subpart
- No
- Authorized official
- Mark Fahlen, President(209) 544-2910
- License
- A81212 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
17 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2008-08-03
- Last updated
- 2011-08-02
Frequently asked questions
- What is Mark T. Fahlen, MD, Inc. a Professional Medical Corporation's NPI number?
- Mark T. Fahlen, MD, Inc. a Professional Medical Corporation's National Provider Identifier (NPI) is 1659537264, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What type of organization is Mark T. Fahlen, MD, Inc. a Professional Medical Corporation?
- Mark T. Fahlen, MD, Inc. a Professional Medical Corporation is classified in the NPPES registry as Nephrology Physician (Allopathic & Osteopathic Physicians).
- Where is Mark T. Fahlen, MD, Inc. a Professional Medical Corporation located?
- Mark T. Fahlen, MD, Inc. a Professional Medical Corporation's practice location on file with NPPES is 1400 Florida Ave, Modesto, CA 95350-4422.
- What is Mark T. Fahlen, MD, Inc. a Professional Medical Corporation's phone number?
- The practice phone number listed in the NPPES registry for Mark T. Fahlen, MD, Inc. a Professional Medical Corporation is (209) 544-2910.
- Does Mark T. Fahlen, MD, Inc. a Professional Medical Corporation accept Medicare?
- Mark T. Fahlen, MD, Inc. a Professional Medical Corporation is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Who is the authorized official for Mark T. Fahlen, MD, Inc. a Professional Medical Corporation?
- The authorized official listed on Mark T. Fahlen, MD, Inc. a Professional Medical Corporation's NPPES record is Mark Fahlen, President. The authorized official registers and maintains the organization's NPI and is not necessarily its owner.
- Is Mark T. Fahlen, MD, Inc. a Professional Medical Corporation's NPI active?
- Yes — Mark T. Fahlen, MD, Inc. a Professional Medical Corporation's NPI (1659537264) is active in the NPPES registry as of the last update on 2011-08-02.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.