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GREGORY H TCHEJEYAN MD INC
NPI 1376835330
Specialist in Thousand Oaks, CA

Active since May 10, 2011
250 LOMBARD ST STE 1, THOUSAND OAKS, CA 91360(805) 495-3687(805) 494-1828 Get Directions Write a Review

NPPES record last updated: March 29, 2022. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Gregory H Tchejeyan Md Inc NPPES

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

GREGORY H TCHEJEYAN MD INC (NPI 1376835330) is a healthcare organization registered as a specialist in Thousand Oaks, California and active in the NPI registry since May 2011. The organization lists Siuke Lili, Manager, as its authorized official.

NPPES Registry Identity

NPI1376835330
Entity TypeOrganization
Primary Taxonomy174400000X
Legal Business NameGREGORY H TCHEJEYAN MD INC
Location Address250 LOMBARD ST STE 1Thousand Oaks, CA 91360-8208
Mailing Address250 Lombard St Ste 1Thousand Oaks, CA 91360-8208 · (805) 495-3687 · Fax (805) 494-1828
Phone(805) 495-3687
Fax(805) 494-1828
Organization SubpartNo
Authorized OfficialSiuke LiliManager · (805) 495-3687
Enumeration DateMay 10, 2011
Last NPPES UpdateMarch 29, 2022
NPPES CertifiedMarch 29, 2022
✔ NPI 1376835330 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtySpecialistOther Service Providers
Taxonomy Code174400000X
License✔ Licensed in CA · A55364
Definition
An individual educated and trained in an applied knowledge discipline used in the performance of work at a level requiring knowledge and skills beyond or apart from that provided by a general education or liberal arts degree.
250 LOMBARD ST STE 1, Thousand Oaks, CA 91360
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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, revalidation and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Gregory H Tchejeyan Md Inc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Medicare Revalidation Due Date

Revalidation due by January 31, 2027

Medicare-enrolled providers and suppliers confirm their enrollment information with CMS on a set cycle, every 5 years for most and every 3 years for medical equipment suppliers. CMS sets the due date for each enrollment.

StateEnrollment IDDue date
StateCaliforniaEnrollment IDO20120228000090Non-DME Part B · Clinic/Group PracticeDue dateJanuary 31, 2027
Source: CMS Revalidation Due Date List, October 2026 release.

Clinicians Billing Medicare Through This Organization

Medicare enrollment records show 1 clinician reassigns Medicare billing to Gregory H Tchejeyan MD Inc, which bills Medicare for the services this clinician delivers.

Clinician (1)

Gregory Tchejeyan, M.D., INC
Orthopedic Surgery
NPI 1689668188
250 LOMBARD ST STE 1
Thousand Oaks, CA 91360
(805) 495-3687
✔ 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 Gregory H Tchejeyan MD Inc's NPI number?

The NPI number for Gregory H Tchejeyan MD Inc is 1376835330. It was assigned to this organization in the NPPES registry on May 10, 2011.

Where is Gregory H Tchejeyan MD Inc located?

Gregory H Tchejeyan MD Inc is located at 250 Lombard St Ste 1, Thousand Oaks, CA 91360. The listed phone number is (805) 495-3687.

What is Gregory H Tchejeyan MD Inc's specialty?

The primary specialty registered for this NPI is Specialist with taxonomy code 174400000X.

Is Gregory H Tchejeyan MD Inc enrolled in Medicare?

Yes. Gregory H Tchejeyan MD Inc is registered in the Medicare PECOS enrollment system.

When is Gregory H Tchejeyan MD Inc's Medicare revalidation due?

According to the CMS Revalidation Due Date List (October 2026 release), the Medicare Non-DME Part B enrollment for this organization (California, Clinic/Group Practice) is due for revalidation by January 31, 2027. Medicare providers and suppliers revalidate their enrollment every 5 years, and medical equipment suppliers every 3 years. Confirm current requirements with your Medicare Administrative Contractor.

How many clinicians bill Medicare through Gregory H Tchejeyan MD Inc?

According to the CMS Revalidation Reassignment List (October 2026 release), 1 clinician (Orthopedic Surgery) reassigns their Medicare billing to Gregory H Tchejeyan MD 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 Gregory H Tchejeyan MD Inc was last updated on March 29, 2022. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 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.