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CLARK S. TSAI, M.D., INC.
NPI 1699944298
Ophthalmology in Concord, CA

Active since February 27, 2008
2225 PORT CHICAGO HWY, CONCORD, CA 94520(925) 689-7744(925) 689-7748 Get Directions Write a Review

NPPES record last updated: December 9, 2011. Verified against the NPPES registry weekly; last sync: November 08, 2026.

About Clark S. Tsai, M.d., Inc. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

CLARK S. TSAI, M.D., INC. (NPI 1699944298) is a healthcare organization registered as an ophthalmology in Concord, California and active in the NPI registry since February 2008. The organization lists Clark Szumin Tsai, Ceo/president, as its authorized official.

NPPES Registry Identity

NPI1699944298
Entity TypeOrganization
Primary Taxonomy207W00000X
Legal Business NameCLARK S. TSAI, M.D., INC.
Location Address2225 PORT CHICAGO HWYConcord, CA 94520-2051
Mailing Address2225 Port Chicago HwyConcord, CA 94520-2051 · (925) 689-7744 · Fax (925) 689-7748
Phone(925) 689-7744
Fax(925) 689-7748
Organization SubpartNo
Authorized OfficialClark Szumin TsaiCeo/president · (925) 689-7744
Enumeration DateFebruary 27, 2008
Last NPPES UpdateDecember 9, 2011
✔ NPI 1699944298 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyOphthalmologyAllopathic & Osteopathic Physicians
Taxonomy Code207W00000X
License✔ Licensed in CA · G76192
Definition
An ophthalmologist has the knowledge and professional skills needed to provide comprehensive eye and vision care. Ophthalmologists are medically trained to diagnose, monitor and medically or surgically treat all ocular and visual disorders. This includes problems affecting the eye and its component structures, the eyelids, the orbit and the visual pathways. In so doing, an ophthalmologist prescribes vision services, including glasses and contact lenses.
2225 PORT CHICAGO HWY, Concord, CA 94520
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Other Identifiers 4

Medicare UPINY27763CA
Medicare NSC5415470001CA
Medicaid00G761922CA
Medicare PINZZZ32492ZCA

Group Practice 1

Group TaxonomyThis provdier is a business group of one or more individual practitioners, all of who practice with the same area of specialization.193400000X SINGLE SPECIALTY GROUP

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Clark S. Tsai, M.d., Inc. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

Medicare enrollment records show 1 clinician reassigns Medicare billing to Clark S. Tsai, M.D., Inc., which bills Medicare for the services this clinician delivers.

Clinician (1)

Clark Tsai, M.D.
Ophthalmology
NPI 1720096829
2700 GRANT ST STE. 100
Concord, CA 94520
(925) 689-7744
✔ PECOS✔ Accepts Medicare0.4 mi

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Clark S. Tsai, M.D., Inc.'s NPI number?

The NPI number for Clark S. Tsai, M.D., Inc. is 1699944298. It was assigned to this organization in the NPPES registry on February 27, 2008.

Where is Clark S. Tsai, M.D., Inc. located?

Clark S. Tsai, M.D., Inc. is located at 2225 Port Chicago Hwy, Concord, CA 94520. The listed phone number is (925) 689-7744.

What is Clark S. Tsai, M.D., Inc.'s specialty?

The primary specialty registered for this NPI is Ophthalmology with taxonomy code 207W00000X.

Is Clark S. Tsai, M.D., Inc. enrolled in Medicare?

Yes. Clark S. Tsai, M.D., Inc. is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Clark S. Tsai, M.D., Inc.?

According to the CMS Revalidation Reassignment List (October 2026 release), 1 clinician (Ophthalmology) reassigns their Medicare billing to Clark S. Tsai, M.D., Inc.. A reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for the clinician's services. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

When was this NPI record last updated?

The NPPES record for Clark S. Tsai, M.D., Inc. was last updated on December 9, 2011. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 14 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.