Medicare Enrolled
Dr. Timothy Byun, MD
Hematology & Oncology · Orange, CA
Practice pattern: Clinical Cardiology
— Primarily office-based clinical cardiology
Speaking/Promotional
Very High
DATA COVERAGE
Data in 4 of 4 federal sources
Measures public federal data availability — not provider quality
Informational, not a quality rating.
This page presents federal public records about Dr. Byun from CMS (NPPES, Open Payments, Medicare Provider Utilization, PECOS). It is not medical advice, an endorsement, or a judgment of clinical quality. Always consult the provider directly and a licensed clinician for medical decisions. Read methodology →
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What this data tells you about Dr. Byun
Dr. Timothy Byun is a hematology & oncology specialist in Orange, CA, with 19 years of NPI registration. Based on federal Medicare data, Dr. Byun performed 1,593 Medicare services across 768 unique beneficiaries.
Between the years covered by Open Payments, Dr. Byun received a total of $124,705 from 101 pharmaceutical and/or device companies across 1483 individual payments. These payments are legal, publicly disclosed under the federal Sunshine Act, and common in hematology & oncology. The majority of payments are for speaking programs and promotional activities, reflecting participation in industry-sponsored events. Patients may wish to discuss these relationships with their provider.
The Data Coverage level for Dr. Byun is Very High — reflecting how much public federal data is available about this provider. Patients are encouraged to use this data as one of several factors when choosing a healthcare provider.
✓ 19 years in practice
▲ Top 43% volume in CA
$124,705 industry payments
Medicare Practice Summary
Medicare Utilization ↗1,593
Medicare services
Top 43% in CA for hematology & oncology
768
Unique beneficiaries
$65
Avg. Medicare payment
Medicare patients only (65+ / disabled) · How to read this →
~84 Medicare services per year of practice
Top procedures by volume
Ranked by number of services performed for Medicare patients. Avg. submitted charge is what the provider billed; avg. Medicare payment is what CMS paid.
| Procedure | Volume | Avg. paid | Avg. submitted |
|---|---|---|---|
| Office visit, established patient (30-39 min) A follow-up office visit for an existing patient lasting between 30 and 39 minutes. The visit involves medical evaluation and management of the patient's condition. |
546 | $101 | $368 |
| Complete blood count (CBC) with differential An automated laboratory test that measures the levels of red blood cells, white blood cells, and platelets in the blood, including a breakdown of the different types of white blood cells. |
261 | $8 | $38 |
| Blood draw (venipuncture) Insertion of a needle into a vein to collect a blood sample. |
257 | $8 | $16 |
| Hospital follow-up visit, high complexity Subsequent hospital inpatient or observation care for an existing patient involving high-level medical decision making, with at least 50 minutes total time on the date of the encounter. |
101 | $96 | $267 |
| Comprehensive metabolic blood panel A blood test that measures a group of chemicals, including glucose, electrolytes, and kidney and liver function markers. |
74 | $10 | $32 |
| Intravenous chemotherapy infusion, 1 hour or less Administration of chemotherapy medication directly into a vein. The procedure takes one hour or less to complete. |
69 | $121 | $463 |
| New patient office visit, complex (60-74 min) | 65 | $170 | $611 |
| Office visit, established patient (20-29 min) An office visit for an existing patient lasting between 20 and 29 minutes. The visit involves medical evaluation and management of the patient's condition. |
51 | $75 | $280 |
| Telephone medical discussion, 11-20 minutes A phone conversation with a physician lasting between 11 and 20 minutes. |
51 | $70 | $258 |
| Drug injection, under skin or into muscle A procedure involving the administration of a medication or substance via injection into the subcutaneous tissue or muscle. |
39 | $12 | $48 |
| Intravenous infusion, 1 hour or less Administration of medication or fluid directly into a vein for therapeutic, preventive, or diagnostic purposes. The procedure lasts one hour or less. |
23 | $59 | $225 |
| Hospital follow-up visit, moderate complexity Follow-up hospital visit for an existing patient involving moderate medical decision making. The visit requires at least 35 minutes of time spent on the date of service. |
23 | $66 | $203 |
| Bone marrow biopsy and aspiration A procedure to remove a small sample of bone marrow and liquid for laboratory testing. The sample is analyzed to help diagnose various medical conditions. |
17 | $143 | $522 |
| Office visit, established patient (10-19 min) An office visit for an existing patient lasting 10 to 19 minutes. The visit involves medical evaluation and management of the patient's condition. |
16 | $43 | $167 |
How to read this data: This reflects Medicare patients only (typically 65+). Payment amounts are what Medicare paid the provider, not your out-of-pocket cost. A higher procedure volume generally indicates more experience with that procedure.
5.8% high complexity
3.5% medium
90.7% routine
Industry Payment Transparency
Open Payments through 2024 ↗$124,705
Total received (2018-2024)
Avg $17,815/year across 7 years
Top 7% in CA for hematology & oncology
A higher payment rank reflects disclosed industry relationships (consulting, research, speaking) common among subspecialists — not wrongdoing.
101
Companies
1,483
Individual payments
All payments are legal and publicly reported · Not evidence of wrongdoing · How to interpret →
Payment profile
Industry payments classified by relationship type. Not all payments are equal — research and consulting reflect different relationships than speaking programs or meals.
Speaking / Promotional
Speaker programs, honoraria, and industry-sponsored educational events
$70,742 (56.7%)
Consulting
Expert advisory fees, typically reflecting recognized clinical expertise
$33,140 (26.6%)
Meals & Travel
Food, beverages, travel, and lodging — typically low-value
$20,823 (16.7%)
Payment trend by year
Annual totals from pharmaceutical and medical device companies.
2024
$6,726
2023
$15,051
2022
$8,631
2021
$8,123
2020
$8,207
2019
$45,858
2018
$32,108
Payments by company (2024)
Consulting
Speaking
Meals & Travel
Research
AstraZeneca Pharmaceuticals LP
$2,072
PFIZER INC.
$537
Novartis Pharmaceuticals Corporation
$486
Merck Sharp & Dohme LLC
$231
Exelixis Inc.
$212
GlaxoSmithKline, LLC.
$203
E.R. Squibb & Sons, L.L.C.
$198
ABBVIE INC.
$191
Sumitomo Pharma America, Inc.
$162
Janssen Biotech, Inc.
$156
ARRAY BIOPHARMA INC
$153
Genentech USA, Inc.
$145
Daiichi Sankyo Inc.
$143
Astellas Pharma US Inc
$140
Gilead Sciences, Inc.
$137
PharmaEssentia USA Corporation
$130
Takeda Pharmaceuticals U.S.A., Inc.
$111
Celgene Corporation
$102
Eisai Inc.
$99
Karyopharm Therapeutics Inc.
$94
Lilly USA, LLC
$80
GENZYME CORPORATION
$78
Regeneron Healthcare Solutions, Inc.
$66
Stemline Therapeutics Inc.
$62
Incyte Corporation
$60
Ipsen Biopharmaceuticals, Inc
$58
SpringWorks Therapeutics, Inc.
$56
BeiGene USA, Inc.
$52
Genmab U.S., Inc.
$50
Boehringer Ingelheim Pharmaceuticals, Inc.
$44
Bayer Healthcare Pharmaceuticals Inc.
$43
TerSera Therapeutics LLC
$38
TAIHO ONCOLOGY, INC.
$34
Pharmacosmos Therapeutics Inc.
$32
Tempus AI, Inc
$29
PUMA BIOTECHNOLOGY, INC.
$28
EMD Serono, Inc.
$28
Blueprint Medicines Corporation
$28
SOBI, INC
$28
Alexion Pharmaceuticals, Inc.
$26
Coherus Biosciences Inc.
$25
ACCORD HEALTHCARE, INC.
$24
ADC Therapeutics America, Inc.
$20
JAZZ PHARMACEUTICALS INC.
$16
Acrotech Biopharma Inc.
$16
Top 3 companies account for 46.0% of 2024 payments
All-time payments by company (2018-2024) ›
Merck Sharp & Dohme Corporation
$39,826
E.R. Squibb & Sons, L.L.C.
$34,619
AstraZeneca Pharmaceuticals LP
$11,830
AbbVie, Inc.
$6,458
Exelixis Inc.
$5,018
Celgene Corporation
$4,380
Novartis Pharmaceuticals Corporation
$1,701
Amgen Inc.
$1,491
Eisai Inc.
$1,481
PFIZER INC.
$1,446
Genentech, Inc.
$1,281
Janssen Scientific Affairs, LLC
$1,148
Seagen Inc.
$928
Genentech USA, Inc.
$859
Janssen Biotech, Inc.
$746
Pharmacyclics LLC, An AbbVie Company
$717
Daiichi Sankyo Inc.
$662
GlaxoSmithKline, LLC.
$522
Gilead Sciences, Inc.
$519
ARRAY BIOPHARMA INC
$474
Merck Sharp & Dohme LLC
$463
GENZYME CORPORATION
$407
Astellas Pharma US Inc
$407
BeiGene USA, Inc.
$400
Takeda Pharmaceuticals U.S.A., Inc.
$385
Bayer HealthCare Pharmaceuticals Inc.
$353
EISAI INC.
$302
Foundation Medicine, Inc.
$298
AbbVie Inc.
$282
Regeneron Healthcare Solutions, Inc.
$271
Sumitomo Pharma America, Inc.
$236
ABBVIE INC.
$234
Myovant Sciences Inc.
$233
EMD Serono, Inc.
$231
Incyte Corporation
$194
Karyopharm Therapeutics Inc.
$190
TerSera Therapeutics LLC
$179
Kite Pharma, Inc.
$177
Coherus Biosciences Inc.
$168
Boehringer Ingelheim Pharmaceuticals, Inc.
$157
Pharmacyclics LLC, an AbbVie Company
$152
PUMA BIOTECHNOLOGY, INC.
$147
PharmaEssentia USA Corporation
$130
Seattle Genetics, Inc.
$128
Puma Biotechnology, Inc.
$124
AMAG Pharmaceuticals, Inc.
$113
Ipsen Biopharmaceuticals, Inc
$94
Bayer Healthcare Pharmaceuticals Inc.
$87
Acceleron Pharma, Inc.
$86
Alnylam Pharmaceuticals Inc.
$82
Genmab U.S., Inc.
$82
Stemline Therapeutics Inc.
$82
Rigel Pharmaceuticals, Inc.
$80
Lilly USA, LLC
$80
MEDIVATION FIELD SOLUTIONS LLC
$78
Array BioPharma Inc.
$78
Alexion Pharmaceuticals, Inc.
$73
Epizyme, Inc.,
$63
Dendreon Pharmaceuticals LLC
$63
SpringWorks Therapeutics, Inc.
$56
Blueprint Medicines Corporation
$56
Deciphera Pharmaceuticals Inc.
$55
EUSA Pharma (US) LLC
$54
Octapharma USA, Inc.
$53
Servier Pharmaceuticals LLC
$44
Taiho Oncology, Inc.
$43
SOBI, INC
$43
JAZZ PHARMACEUTICALS INC.
$41
ADC Therapeutics America, Inc.
$41
AVEO Pharmaceuticals, Inc.
$40
MorphoSys, US Inc.
$38
TAIHO ONCOLOGY, INC.
$34
Acrotech Biopharma Inc.
$33
West Therapeutics Development, LLC
$33
Pharmacosmos Therapeutics Inc.
$32
Lexicon Pharmaceuticals, Inc.
$32
Dova Pharmaceuticals
$30
CSL Behring
$30
Tempus AI, Inc
$29
Sirtex Medical Inc
$26
Teva Pharmaceuticals USA, Inc.
$25
Secura Bio, Inc.
$25
TESARO, Inc.
$24
Clovis Oncology, Inc.
$24
ACCORD HEALTHCARE, INC.
$24
Blue Earth Diagnostics Limited
$24
Acrotech Biopharma LLC
$24
Abbott Laboratories
$22
Jazz Pharmaceuticals Inc.
$19
SERVIER PHARMACEUTICALS LLC
$18
Mylan Institutional Inc.
$16
Emmaus Medical, Inc.
$16
Helsinn Therapeutics (U.S.), Inc.
$15
Spectrum Pharmaceuticals Inc.
$15
Kyowa Kirin, Inc.
$14
Sobi, Inc
$13
SANOFI-AVENTIS U.S. LLC
$12
CTI BioPharma Corp.
$12
Heron Therapeutics, Inc.
$11
Aurobindo Pharma USA, Inc.
$11
Janssen Pharmaceuticals, Inc
$2
Top 3 companies account for 69.2% of all-time payments
Associated products mentioned in payments ›
ABECMA · ADCETRIS · AFINITOR · AKYNZEO · ALUNBRIG · AYVAKIT · Actemra · Alecensa · Aliqopa · Aranesp · Avastin · Axumin · BAVENCIO · BELEODAQ · BENDEKA · BESREMI · BLENREP · BOSULIF · BRAFTOVI · BRUKINSA · Balversa · Bavencio · Beleodaq · Blincyto · Braftovi · CABLIVI · CABOMETYX · CALQUENCE · CAMCEVI · CAPRELSA · CARVYKTI · CHANTIX · CINVANTI · Cabometyx · Columvi · DARZALEX · Doptelet · ELIQUIS · ELITEK · ELZONRIS · EMPLICITI · ENHERTU · EPKINLY · ERLEADA · Endari · Enhertu · Epkinly · Erleada · FARYDAK · FERAHEME · FOTIVDA · FOUNDATIONONE · FRUZAQLA · Fabhalta · Farydak · Folotyn · Fulphila · GAMIFANT · GAZYVA · GILOTRIF · GIVLAARI · HEMADY · Halaven · Herceptin · IBRANCE · ICLUSIG · IMBRUVICA · IMFINZI · INJECTAFER · INLYTA · INQOVI · INREBIC · Idelvion · Imbruvica · Inrebic · Itovebi · JADENU · JAKAFI · JEMPERLI · JEVTANA · KANJINTI · KEYTRUDA · KISQALI · Kyprolis · LIBTAYO · LONSURF · LORBRENA · LUMAKRAS · LUTATHERA · LYNPARZA · Lazanda · Lenvima · Lonsurf · Lupron · MEKINIST · MONJUVI · MONOFERRIC · MYLOTARG · Mitra Clip system · NERLYNX · NINLARO · Nerlynx · Neulasta · Nplate · Nubeqa · OGSIVEO · OJJAARA · ONUREG · OPDIVO · OPDUALAG · ORGOVYX · Onivyde · Orserdu · PADCEV · PEMAZYRE · PIQRAY · PLUVICTO · POTELIGEO · PROMACTA · PROVENGE · Padcev · Perjeta · Phesgo · Polivy · Pomalyst · Prolia · QINLOCK · REBLOZYL · RETACRIT · RYBREVANT · Reblozyl · Revlimid · Rezlidhia · Rubraca · SANDOSTATIN LAR · SARCLISA · SCEMBLIX · SIR-Spheres Microspheres · SOMATULINE DEPOT · SUTENT · SYNAGIS · Stivarga · Sylvant · TAGRISSO · TALVEY · TASIGNA · TAZVERIK · TECENTRIQ · TECVAYLI · TIBSOVO · TIVDAK · TUKYSA · TUMOR LYSIS SYNDROME - DISEASE · Tavalisse · Tecentriq · Trodelvy · ULTOMIRIS · Udenyca · Ultomiris · VARUBI · VENCLEXTA · VERZENIO · VOTRIENT · VPRIV · VYXEOS · Vanflyta · Vectibix · Venclexta · Vonjo · Vyloy · WILATE · XALKORI · XARELTO · XERMELO · XGEVA · XOSPATA · XPOVIO · XTANDI · Xermelo · Xofigo · Xospata · Xtandi · Yescarta · ZEJULA · ZEPZELCA · ZOLADEX · Zoladex
Should you be concerned? Payments from pharmaceutical and device companies are legal and common — 57% of U.S. physicians receive at least one. They often reflect legitimate consulting, research, or education. What matters is whether a recommended drug or device appears in your doctor's payment records. If so, consider asking your doctor about it. How to interpret this data →
The majority of payments (57%) are for speaking programs and promotional activities, which reflect participation in industry-sponsored educational or marketing events. This is common in hematology & oncology and does not inherently indicate bias, but patients may wish to be aware. Total industry engagement is in the top 7% for hematology & oncology in CA.
Geographic Context
Hematology & oncology specialists within 10 mi
243
Per 100K population
7.7
County median income
$113,702
Nearest hospital
PROVIDENCE ST. JOSEPH HOSPITAL
0.0 mi
0.0 mi
Data Sources
| Provider Registry | ✓ NPPES | Weekly updates |
| Medicare Enrollment | ✓ PECOS | Monthly updates |
| Practice Data | ✓ Medicare Util. | Annual (CY lag) |
| Industry Payments | ✓ Open Payments | CY 2024 |
| Disciplinary History | — Not public | N/A |
This provider has data in 4 of 4 available federal datasets, with a Data Coverage level of Very High. This reflects how much public data is available about a provider. How we calculate this →
Summary
Dr. Byun is a clinical cardiology specialist, with moderate Medicare volume, with speaking/promotional industry engagement in the top 7% of CA peers, with 19 years of NPI registration.
This summary is auto-generated from federal data, describing data availability and patterns. Read our methodology →
Frequently Asked Questions
Is Dr. Byun experienced with office visit, established patient (30-39 min)?
Based on Medicare claims data, Dr. Byun performed 546 office visit, established patient (30-39 min) services. Research suggests that higher procedure volume is often associated with better outcomes, particularly for complex procedures. Note that Medicare data only captures patients aged 65 and older, so the total practice volume across all patients is likely higher.
Does Dr. Byun receive payments from pharmaceutical companies?
Yes. Dr. Byun received a total of $124,705 from 101 companies across 1,483 individual payments. These payments are legal, publicly disclosed under the federal Sunshine Act, and common among physicians — 57% of all U.S. physicians receive at least one industry payment. Patients may wish to ask their doctor about these relationships, especially if a recommended drug or device appears in the payment records.
How do Dr. Byun's costs compare to other hematology & oncology specialists in Orange?
Dr. Byun's average Medicare payment per service is $65. Note that these figures represent what Medicare pays, not your out-of-pocket cost, which depends on your specific insurance plan and deductible. Procedure-level data above shows both what was submitted and what Medicare paid for each service type.
What does Data Coverage mean?
Data Coverage (currently Very High for Dr. Byun) measures how much public federal data is available about a provider. It is not a quality rating. A "Very High" or "High" level means the provider has data across multiple federal sources (NPPES, PECOS, Medicare Utilization, Open Payments), indicating a long track record of practice, Medicare participation, and industry disclosure. A "Low" or "Moderate" level may simply mean the provider is newer, does not see Medicare patients, or has not received any industry payments — none of which are inherently negative. Read our full methodology →
Is this data up to date?
Each data source has its own update cycle. Provider registry data (NPPES) is updated weekly. Medicare enrollment (PECOS) is updated monthly. Medicare practice data has a ~2 year lag — the most recent available is typically 2 years prior. Industry payment data (Open Payments) is published annually, usually in June, covering the prior calendar year. We display the data date prominently on each section so you always know how current it is. See our data freshness policy →
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About this page
All data on this page is sourced verbatim from public federal records published by the U.S. Centers for Medicare & Medicaid Services (CMS): NPPES ↗, Open Payments ↗, Medicare Provider Utilization ↗, and PECOS. Publication is mandated by the Physician Payments Sunshine Act (§6002 ACA, 42 U.S.C. §1320a-7h) and the Freedom of Information Act.
This page is not medical advice, an endorsement, a recommendation, or a quality rating. Data Coverage reflects data completeness — how much federal information exists for this provider — not clinical performance, patient outcomes, or quality of care. Always verify information directly with the provider and consult a licensed clinician before making medical decisions.
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