NPI registry status
Active
2026 NPPES data Research Study Specialist NPI 1538407721 M.D.
Verify on CMS → Jonathan Leff, M.D.
Research Study Specialist in Menlo Park, California.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 508 in Research Study Specialist, and covers specialty classification, practice address, and Medicare Part D prescribing data when reported. According to CMS, every field reflects the provider's official federal registration, see our methodology.
Federal data, no proprietary rating.
We show these CMS records as-is - no composite score, no star rating, no editorial opinion layered on top.
Industry payments
$138.83
1 payments · CMS Open Payments (Sunshine Act)
What the federal data shows
Jonathan Leff, M.D. is a Research Study Specialist in Menlo Park, California, listed in the federal CMS National Provider Identifier registry.
- $138.83
- industry payments (Sunshine Act)
- #293
- Research Study Specialist rank among California specialties
Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) - no proprietary rating or editorial opinion is applied.
Federal trust snapshot
What official records show about Jonathan Leff, M.D.
Bare NPI registry listing — limited federal enrichment beyond basic enumeration. Verify all credentials with official sources.
- Verified
NPI registry status
Active listing in the CMS National Provider Identifier Registry (NPI 1538407721), first enumerated 01/22/2013.
Source: CMS NPPES
- Not in federal data
Medicare Part D participation
No 2023 Medicare Part D prescribing volume appears in the CMS public file for this NPI (may reflect specialty, new enrollment, or non-prescribing role).
Source: CMS Part D Prescriber PUF
- Reported
Industry payment transparency
$138.83 in reported industry payments (1 transfers) in 2024 under the federal Sunshine Act — disclosed transfers of value, not a quality rating.
Source: CMS Open Payments
- State context
State board disciplinary context
California statewide board action statistics are published annually — these figures describe aggregate state activity, not Jonathan Leff, M.D.'s individual license status. Verify directly with the state medical board.
Source: MBC annual report 2023
- Not in federal data
Individual sanction lookup
PlainDoctor does not publish per-provider disciplinary determinations. Confirm current license and any individual actions through the state medical board or FSMB verification service.
Source: State medical board / FSMB
This trust snapshot summarizes only what appears in federal CMS/NPPES public records. It is not a composite score, star rating, patient review, or clinical recommendation. PlainDoctor never fabricates reviews or AggregateRating schema.
CMS NPPES provider registry desk
NPI 1538407721 · Research Study Specialist
NPI-10 · ENUM-MID · TAX-NARROW · RX-NONE · BOOK-THIN · PHOTO-ENUM
- NPI-10 1538407721
- ENUM-MID 2013
- TAX-NARROW 508
- RX-NONE No Part D
- BOOK-THIN 84 in California
- PHOTO-ENUM Aaron Becker · 2013
What does the federal data show about Jonathan Leff, M.D.?
Quality data not reportedPrimary specialty
Research Study Specialist
Specialty distribution in California
How Research Study Specialist compares to other specialties among California providers
Board certification
Not published by CMS
CMS does not publish a per-provider board-certification field in NPPES. PlainDoctor does not have a reliable per-specialty certification rate to show for Research Study Specialist. Verify directly:
How MIPS and board certification work
The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.
Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).
Practice Address
Provider Details
| NPI | 1538407721 |
|---|---|
| Specialty | Research Study Specialist |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 01/22/2013 |
Industry payments received (2024) - CMS Open Payments transparency data
The federal Physician Payments Sunshine Act (part of the Affordable Care Act) requires drug and medical-device manufacturers + group purchasing organizations to publicly report payments and other transfers of value to physicians and teaching hospitals. The data below covers 2024 for Jonathan Leff, M.D.. Source: openpaymentsdata.cms.gov.
Total received
$139
Largest payer
Genentech USA, Inc.
Most common payment type
Food and Beverage
Industry payments are not necessarily indicators of bias, they include research funding, consulting fees for evidence-based work, royalties for inventions, food at conferences, and similar items. The disclosure exists for transparency. Read our methodology for how we interpret this data.
License & disciplinary context - California MBC 2023 annual report
Aggregate state board data only, NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~150K California medical licensees in 2023 - they are NOT specific to Jonathan Leff, M.D.. To verify Jonathan Leff, M.D.'s current license status, search the MBC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
576
Total board actions, California 2023
Across 556 cases
3.84
Actions per 1,000 licensees
California statewide rate
probation
Most common action type
186 cases
MBC publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the California disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Research Study Specialist Overview
How Jonathan Leff, M.D. fits within the Research Study Specialist landscape nationally.
508
Research Study Specialist Providers in US
42
States with Research Study Specialist
922
Avg Claims per Provider
Nationwide Research Study Specialist peers with similar MIPS or enrollment year
Two federal-record peer sets for Leff, both outside California so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2013)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Research Study Specialist Providers in California
Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as Leff.
One of 84 Research Study Specialist providers enrolled in California, 5 are shown here.
Dr. Diana Abdulrahman
M.D.
Pomona, CA
Dr. Kristen Aiemjoy
PHD
Davis, CA
Dr. David Angert
M.D./PH.D
Long Beach, CA
Dr. Naama Barnea-Goraly
M.D.
Menlo Park, CA
Ignacio Baselga
Venice, CA
Compare Research Study Specialist nationally: see state-by-state distribution →
Frequently Asked Questions
What is Jonathan Leff, M.D.'s specialty? ▼
Jonathan Leff, M.D. specializes in Research Study Specialist and practices in Menlo Park, California. Credentials: M.D..
Where is Jonathan Leff, M.D. located? ▼
Jonathan Leff, M.D. is located at 178 SEMINARY DR, Menlo Park, CA, 94025. Phone: (650) 521-0353.
What is Jonathan Leff, M.D.'s NPI number? ▼
Jonathan Leff, M.D.'s National Provider Identifier (NPI) is 1538407721, issued on 01/22/2013.
How many Research Study Specialist providers are there in the US? ▼
There are 508 Research Study Specialist providers across 42 states in the US. The average Research Study Specialist provider writes 922 Medicare Part D claims per year.
Does Jonathan Leff, M.D. accept Medicare? ▼
Jonathan Leff, M.D. appears in CMS Medicare data. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Jonathan Leff, M.D.'s credentials? ▼
Jonathan Leff, M.D.'s NPI is 1538407721 with credentials M.D.. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.
Data Sources
View source datasets and methodology notes
- Provider Directory
- CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
- Specialty Classification
- NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
- Limitations
- Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.
See our complete data methodology for details on how we collect and process government data.
Data as of August 2026 (NPPES) / 2024 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).
Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology
Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of August 2026.