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Karl Gerard Sylvester, M.D.

Pediatric Surgery Physician in Palo Alto, CA · enumerated 2007.

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

National Provider Identifier

1285784538

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Registry record

Entity type Individual (Type 1)
Name Karl Gerard Sylvester
Credential M.D.
Sex Male
Practice address 725 Welch Rd, Palo Alto, CA, 94304
Phone (650) 497-8000
Fax (650) 725-5577
Enumeration date Jan 11, 2007
Last updated in NPPES Apr 29, 2024

Taxonomy & licenses

2086S0120X Pediatric Surgery Physician Allopathic & Osteopathic Physicians · License G86149 (CA) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

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

How do I verify Karl Sylvester's NPI record?
Cross-check NPI 1285784538 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1285784538 active?
Yes, as of the latest NPPES snapshot, NPI 1285784538 is active (record last updated 2024-04-29).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2024-04-29.