Marcus Mayus Md INC in Greenwich, CT
This organization bills under NPI 1780341743, an organization record issued on Nov 24, 2021 with the primary taxonomy Internal Medicine Physician. Each clinician who works there has their own NPI and license.
Organization recordNPPES, Aug 2026
1780341743
- Legal name
- Marcus Mayus Md INC
- Entity
- Type 2 · organization
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- Practice location
- 81 HOLLY HILL LN FL 3, Greenwich, CT 06830
- Phone
- 203-869-5515
- Enumerated
- Nov 24, 2021
- Record updated
- Nov 24, 2021
- Authorized official
- Physician/Owner (title as filed)
2 clinicians CMS lists with Marcus Mayus Md in Greenwich
- David Lo, MDInternal Medicine Physician1841602273
- Marcus Mayus, MDInternal Medicine Physician1073734935
Source: CMS Doctors and Clinicians group affiliations, matched by practice name and city.
Checking an organization
- Confirm the business with the Connecticut secretary of state.
- Check the HHS-OIG exclusion list for the organization.
- Verify each clinician on their own record and the state license search.
Common questions
Is an organization NPI a license?
No. An NPI identifies who bills. Facilities and the clinicians who work there are licensed separately by the state.
Source: CMS National Plan and Provider Enumeration System (NPPES), monthly file of Aug 9, 2026 (NPPES files on CMS.gov). An NPI identifies who bills; it is not a license.