Dr Mark Jacob Siedner, MD - Medicare Infectious Disease in Boston, MA

Dr Mark Jacob Siedner, MD is a medicare enrolled "Internal Medicine - Infectious Disease" physician in Boston, Massachusetts. He went to Johns Hopkins University School Of Medicine and graduated in 2007 and has 17 years of diverse experience with area of expertise as Infectious Disease. He is a member of the group practice Massachusetts General Physicians Organization Inc and his current practice location is 55 Fruit St, Massachusetts General Hospital Grj504, Boston, Massachusetts. You can reach out to his office (for appointments etc.) via phone at (617) 726-3812.

Dr Mark Jacob Siedner is licensed to practice in Massachusetts (license number 253779) and he also participates in the medicare program. He accepts medicare assignments (which means he accepts the Medicare-approved amount; you will not be billed for any more than the Medicare deductible and coinsurance) and his NPI Number is 1548429178.

Contact Information

Dr Mark Jacob Siedner, MD
55 Fruit St, Massachusetts General Hospital Grj504,
Boston, MA 02114-2621
(617) 726-3812
Not Available

Map and Direction




Physician's Profile

Full NameDr Mark Jacob Siedner
GenderMale
SpecialityInfectious Disease
Experience17 Years
Location55 Fruit St, Boston, Massachusetts
Accepts Medicare AssignmentsYes. He accepts the Medicare-approved amount; you will not be billed for any more than the Medicare deductible and coinsurance.
  Medical Education and Training:
  • Dr Mark Jacob Siedner attended and graduated from Johns Hopkins University School Of Medicine in 2007
  NPI Data:
  • NPI Number: 1548429178
  • Provider Enumeration Date: 06/09/2008
  • Last Update Date: 12/08/2012
  Medicare PECOS Information:
  • PECOS PAC ID: 3971756107
  • Enrollment ID: I20130402000058

Medical Identifiers

Medical identifiers for Dr Mark Jacob Siedner such as npi, medicare ID, medicare PIN, medicaid, etc.
IdentifierTypeStateIssuer
1548429178NPI-NPPES

Medical Taxonomies and Licenses

TaxonomyTypeLicense (State)Status
207RI0200XInternal Medicine - Infectious Disease 253779 (Massachusetts)Primary

Medical Facilities Affiliation

Facility NameLocationFacility Type
Massachusetts General HospitalBoston, MAHospital

Group Practice Association

Group Practice NameGroup PECOS PAC IDNo. of Members
Massachusetts General Physicians Organization Inc24663658203084

Medicare Reassignments

Some practitioners may not bill the customers directly but medicare billing happens through clinics / group practice / hospitals where the provider works. Medicare reassignment of benefits is a mechanism by which practitioners allow third parties to bill and receive payment for medicare services performed by them. Dr Mark Jacob Siedner allows following entities to bill medicare on his behalf.
Entity NameMassachusetts General Physicians Organization Inc
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1801874573
PECOS PAC ID: 2466365820
Enrollment ID: O20031111000434
Entity NameThe General Hospital Corporation
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1023049236
PECOS PAC ID: 6507803806
Enrollment ID: O20080313000351

Medicare Part D Prescriber Enrollment

Any physician or other eligible professional who prescribes Part D drugs must either enroll in the Medicare program or opt out in order to prescribe drugs to their patients with Part D prescription drug benefit plans. Dr Mark Jacob Siedner is enrolled with medicare and thus, if eligible, can prescribe medicare part D drugs to patients with medicare part D benefits.

Mailing Address and Practice Location

Mailing AddressPractice Location Address
Dr Mark Jacob Siedner, MD
55 Fruit St, Massachusetts General Hospital, Grj-504,
Boston, MA 02114-2621

Ph: () -
Dr Mark Jacob Siedner, MD
55 Fruit St, Massachusetts General Hospital Grj504,
Boston, MA 02114-2621

Ph: (617) 726-3812

Reviews and Comments


Internal Medicine Doctors in Boston, MA

Kaitlyn My-tu Lam, MBBS
Infectious Disease
Medicare: Not Enrolled in Medicare
Practice Location: Massachusetts General Hospital, 55 Fruit Street, Boston, MA 02114
Phone: 617-724-7738    
Kui Toh Gerard Leong, M.D.
Infectious Disease
Medicare: Not Enrolled in Medicare
Practice Location: 55 Fruit Street, Massachusetts General Hospital, Boston, MA 02114
Phone: 617-726-8862    
Ruma Rajbhandari,
Infectious Disease
Medicare: Accepting Medicare Assignments
Practice Location: 75 Francis St, Boston, MA 02115
Phone: 617-525-6841    
Alaka Ray, M.D.
Infectious Disease
Medicare: Accepting Medicare Assignments
Practice Location: Massachusetts General Hospital, 55 Fruit Street, Boston, MA 02114
Phone: 617-726-2066    
Meghan E Sise, M.D.
Infectious Disease
Medicare: Accepting Medicare Assignments
Practice Location: Massachusetts General Hospital, 55 Fruit Street, Boston, MA 02114
Phone: 617-726-2862    
Aaron Dickstein, M.D.
Infectious Disease
Medicare: Accepting Medicare Assignments
Practice Location: 800 Washington St, Box 233, Boston, MA 02111
Phone: 617-636-5883    Fax: 617-636-9292
Dr. Felicia Elizabeth Patch, MD
Infectious Disease
Medicare: Accepting Medicare Assignments
Practice Location: 801 Massachusetts Ave, Crosstown 2, Boston, MA 02118
Phone: 617-414-4376    Fax: 617-414-4676

Medicare Program: Medicare is a federal government program which provides health insurance to people who are 65 or older. This program also covers certain younger people with disabilities (who receive Social Security Disability Insurance - SSDI), and people with End-Stage Renal Disease (permanent kidney failure requiring dialysis or a transplant, sometimes called ESRD.

Medicare Assignment: Assignment means that your doctor, provider, or supplier agrees (or is required by law) to accept the Medicare-approved amount as full payment for covered services. Most doctors, providers, and suppliers accept assignment, but you should always check to make sure. Participating providers have signed an agreement to accept assignment for all Medicare-covered services.

NPI Number: The National Provider Identifier (NPI) is a unique identification number for covered health care providers. The NPI must be used in lieu of legacy provider identifiers in the HIPAA standards transactions. Covered health care providers and all health plans and health care clearinghouses must use the NPIs in the administrative and financial transactions adopted under HIPAA (Health Insurance Portability and Accountability Act).

Our Data: Information on www.medicarelist.com is built using data sources published by Centers for Medicare & Medicaid Services (CMS) under Freedom of Information Act (FOIA). The information disclosed on the NPI Registry are FOIA-disclosable and are required to be disclosed under the FOIA and the eFOIA amendments to the FOIA. There is no way to 'opt out' or 'suppress' the NPPES record data for health care providers with active NPIs.