Lobbyists having MSD as a client
- APCO Worldwide
- Burson Cohn & Wolfe Sprl
- Edelman Public Relations Worldwide
- hanover communications international
- Hanover Communications International
- Incisive Health
- Rud Pedersen Public Affairs Brussels
- SFL Regulatory Affairs & Scientific Communication GmbH
- The Health Policy Partnership
- UTOPIA LAB S.R.L.