- MB Financial Bank
- MBET Health
- McBee
- McDonnell Construction
- McGuire Group
- McGuireWoods
- McKinsey & Co.
- MCS Plan
- MDA Capital Group
- MDS Consultant LLC
- Meadowbrook Post-Acute
- MED Healthcare Partners
- MedaSync
- MedCity News
- Médecins Sans Frontières
- MedEquities
- MedEquities Realty Trust
- Medica
- Medicaid
- Medicaid and CHIP Payment and Access Commission