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Observatory Surgery Center LLC.

Ambulatory Surgical Clinic/Center in Ukiah, CA · enumerated 2010 · authorized official Harry Matossian, MD/ Owner.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1083944375

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Registry record

Entity type Organization (Type 2)
Legal business name Observatory Surgery Center LLC.
Practice address 271 Observatory Ave, Ukiah, CA, 95482
Phone (707) 462-2299
Fax (707) 462-1194
Enumeration date Jan 8, 2010
Last updated in NPPES Jan 8, 2010

Taxonomy & classification

261QA1903X Ambulatory Surgical Clinic/Center Ambulatory Health Care Facilities Primary

Authorized official

Name Harry Matossian
Title MD/ Owner
Phone (707) 462-0681

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

Who is the authorized official for Observatory Surgery Center LLC.?
NPPES lists Harry Matossian (MD/ Owner) as the authorized official for this organization.
What is the NPI number for Observatory Surgery Center LLC.?
The NPI for Observatory Surgery Center LLC. is 1083944375, a Type 2 (organization) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2010-01-08.