RTH has agreed a four-year contract with United Technologies worth £6m. The three other deals are with German manufacturer Trumpf, pharmaceutical outfit Eli Lilly, and aerospace company Textron.
The agreements cover stand design and build, graphics, on-site management, breakdown and storage and logistics services.
RTH global business development director Claire Edwards said: "We are winning business because we are able to offer sustainable programmes and give clients value for money when budgets are being cut. We can design big stands that can be reconfigured and reused rather than thrown away."