DR MASON LANG OD INC
NPI 1689333502
Optometrist in Union City, CA

Q: What is Dr Mason Lang Od Inc's NPI number?

The NPI number for Dr Mason Lang Od Inc is 1689333502. It was assigned to this organization in the NPPES registry on December 8, 2021. The provider is doing business as Open Eye Optometry.

Q: What is Dr Mason Lang Od Inc's specialty?

The primary specialty registered for this NPI is Optometrist with taxonomy code 152W00000X.

Active since December 08, 2021

30600 DYER ST, UNION CITY, CA 94587(510) 431-3142(510) 324-8591 Get Directions Write a Review

NPPES record last updated: July 12, 2025. Verified against the NPPES registry weekly; last sync: November 01, 2026.

Record update history: Jul 12, 2025, Dec 8, 2021 (2 updates tracked since 2021).

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About Dr Mason Lang Od Inc NPPES

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

DR MASON LANG OD INC (NPI 1689333502), doing business as Open Eye Optometry, is a healthcare organization registered as an optometrist in Union City, California and active in the NPI registry since December 2021. The organization maintains a secondary practice location in Gilroy and lists Mason Lang, Owner, as its authorized official.

NPPES Registry Identity

NPI1689333502

Entity TypeOrganization

Primary Taxonomy152W00000X

Legal Business NameDR MASON LANG OD INC

Location Address30600 DYER STUnion City, CA 94587-1717

Mailing Address500 Pawnee PlFremont, CA 94539-3306 · (510) 456-5848

Phone(510) 431-3142

Fax(510) 324-8591

Organization SubpartNo

Authorized OfficialMason LangOwner · (510) 456-5848

Enumeration DateDecember 8, 2021

Last NPPES UpdateJuly 12, 20252 updates tracked since enumeration

NPPES CertifiedJuly 12, 2025

✔ NPI 1689333502 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyOptometristEye and Vision Services Providers

Taxonomy Code152W00000X

Definition

Doctors of optometry (ODs) are the primary health care professionals for the eye. Optometrists examine, diagnose, treat, and manage diseases, injuries, and disorders of the visual system, the eye, and associated structures as well as identify related systemic conditions affecting the eye. An optometrist has completed pre-professional undergraduate education in a college or university and four years of professional education at a college of optometry, leading to the doctor of optometry (O.D.) degree. Some optometrists complete an optional residency in a specific area of practice. Optometrists are eye health care professionals state-licensed to diagnose and treat diseases and disorders of the eye and visual system.

30600 DYER ST, Union City, CA 94587

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Other Names 1

Doing Business AsOpen Eye Optometry

Secondary Practice Location 1

Location 17150 Camino ArroyoGilroy, CA 95020-7351 · Phone (408) 848-1868

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)

Dr Mason Lang Od 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 Dr Mason Lang Od Inc, which bills Medicare for the services this clinician delivers.

Clinician (1)

Mason Lang, OD

Optometry

NPI 1407337439

30600 DYER ST
Union City, CA 94587

(510) 431-3142

✔ PECOS✔ Accepts MedicareSame address

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 Dr Mason Lang Od Inc's NPI number?

The NPI number for Dr Mason Lang Od Inc is 1689333502. It was assigned to this organization in the NPPES registry on December 8, 2021. The provider is doing business as Open Eye Optometry.

Where is Dr Mason Lang Od Inc located?

Dr Mason Lang Od Inc is located at 30600 Dyer St, Union City, CA 94587. The listed phone number is (510) 431-3142.

What is Dr Mason Lang Od Inc's specialty?

The primary specialty registered for this NPI is Optometrist with taxonomy code 152W00000X.

Is Dr Mason Lang Od Inc enrolled in Medicare?

Yes. Dr Mason Lang Od Inc is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Dr Mason Lang Od Inc?

According to the CMS Revalidation Reassignment List (October 2026 release), 1 clinician (Optometry) reassigns their Medicare billing to Dr Mason Lang Od 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 Dr Mason Lang Od Inc was last updated on July 12, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 15 months 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.