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NATALIE CAC
NPI 1205006657
Allergy & Immunology in Hayward, CA

Active since March 01, 2008PECOS Enrolled
27303 SLEEPY HOLLOW AVE S, HAYWARD, CA 94545(510) 784-6225 Get Directions Write a Review

NPPES record last updated: November 8, 2024. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Nov 8, 2024, May 27, 2022, Nov 29, 2021 and 5 more (8 updates tracked since 2017).

About Natalie Cac NPPES

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

NATALIE CAC (NPI 1205006657) is an individual allergy & immunology provider in Hayward, California, licensed in California (A102269) and active in the NPI registry since March 2008. She is enrolled in Medicare PECOS and maintains a secondary practice location in Fremont.

NPPES Registry Identity

NPI1205006657
Entity TypeIndividualFemale
Primary Taxonomy207K00000X
Provider Legal NameNATALIE CAC
Location Address27303 SLEEPY HOLLOW AVE SHayward, CA 94545-4203
Mailing Address27303 Sleepy Hollow Ave SHayward, CA 94545-4203 · (107) 846-2255
Phone(510) 784-6225
Sole ProprietorNo
Enumeration DateMarch 1, 2008
Last NPPES UpdateNovember 8, 20248 updates tracked since enumeration
NPPES CertifiedNovember 8, 2024
✔ NPI 1205006657 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyAllergy & ImmunologyAllopathic & Osteopathic Physicians
Taxonomy Code207K00000X
Licenses✔ Licensed in CA · A102269✔ Licensed in AZ · 48106
Definition
An allergist-immunologist is trained in evaluation, physical and laboratory diagnosis, and management of disorders involving the immune system. Selected examples of such conditions include asthma, anaphylaxis, rhinitis, eczema, and adverse reactions to drugs, foods, and insect stings as well as immune deficiency diseases (both acquired and congenital), defects in host defense, and problems related to autoimmune disease, organ transplantation, or malignancies of the immune system.
27303 SLEEPY HOLLOW AVE S, Hayward, CA 94545
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Secondary Practice Location 1

Location 139400 Paseo Padre PkwyFremont, CA 94538-2310 · Phone (510) 248-3188

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Natalie Cac is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show Natalie Cac reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Permanente Medical Group Inc
12 mi
Internal Medicine
1190 VETERANS BLVD
Redwood City, CA 94063
  • Reassigned Medicare billing, California enrollment
  • 20,078 clinicians in this Medicare group
NPI 1639252604 (650) 299-2000

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

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

GEORGE LAI M.D.
Internal Medicine (Nephrology)
27303 SLEEPY HOLLOW AVE S
HAYWARD, CA 94545
Alameda County (510) 454-1000
ELAINE K ONG M.D.
Pediatrics
27303 SLEEPY HOLLOW AVE S
HAYWARD, CA 94545
Alameda County (510) 454-1000
DAYNA TAI
Pharmacist
27303 SLEEPY HOLLOW AVE S
HAYWARD, CA 94545
Alameda County (510) 784-4589
RANGASHREE VARADARAJAN MD
Internal Medicine (Nephrology)
27303 SLEEPY HOLLOW AVE S
HAYWARD, CA 94545
Alameda County (510) 784-2769
ARMANDO LASARO PLATA M.D.
Urology
27303 SLEEPY HOLLOW AVE S
HAYWARD, CA 94545
Alameda County (510) 454-1000
LUCY OANH PHUONG M.D.
Pediatrics
27303 SLEEPY HOLLOW AVE S
HAYWARD, CA 94545
Alameda County (510) 454-1000
OLGA LEMBERG MD
Pediatrics
27303 SLEEPY HOLLOW AVE S
HAYWARD, CA 94545
Alameda County (510) 752-1000
MARIO BERNABA MD
Internal Medicine (Nephrology)
27303 SLEEPY HOLLOW AVE S
HAYWARD, CA 94545
Alameda County (510) 784-2769

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 Natalie Cac's NPI number?

The NPI number for Natalie Cac is 1205006657. It was assigned to this individual provider in the NPPES registry on March 1, 2008.

Where is Natalie Cac located?

Natalie Cac practices at 27303 Sleepy Hollow Ave S, Hayward, CA 94545. The listed phone number is (510) 784-6225.

What is Natalie Cac's specialty?

The primary specialty registered for this NPI is Allergy & Immunology with taxonomy code 207K00000X.

Is Natalie Cac enrolled in Medicare?

Yes. Natalie Cac is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Natalie Cac's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Natalie Cac reassigns Medicare benefits to Permanente Medical Group Inc (Redwood City, CA). The 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 Natalie Cac's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Natalie Cac was last updated on November 8, 2024. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 23 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.