Mark Lay, M.D.
NPI 1003803313 · Family Medicine Physician · Cassopolis, MI
Mark Lay, M.D. is a Family Medicine Physician provider in Cassopolis, MI (NPI 1003803313).
Provider details
- NPI number
- 1003803313
- Entity type
- Individual
- Primary specialty
- Family Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- 236771 (NY)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
20 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
- 2005-10-03
- Last updated
- 2007-07-08
Frequently asked questions
- What is Mark Lay's NPI number?
- Mark Lay's National Provider Identifier (NPI) is 1003803313, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Lay's specialty?
- Mark Lay is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Mark Lay located?
- Mark Lay's practice location on file with NPPES is 117 S Broadway St, Cassopolis, MI 49031-1242.
- What is Mark Lay's phone number?
- The practice phone number listed in the NPPES registry for Mark Lay is (269) 445-0771.
- Is Mark Lay's NPI active?
- Yes — Mark Lay's NPI (1003803313) is active in the NPPES registry as of the last update on 2007-07-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.