Royal IHC or Koninklijke IHC, previously IHC Holland (1943–1995), IHC Holland Merwede (1995–2005) and IHC Merwede (2005–2014) is a Dutch shipbuilding company with headquarters in Kinderdijk. It focuses on the development, design and construction of ships for the dredging and offshore industries.

The Industriële Handels Combinatie (IHC) in the Hague was a partnership. The idea came up when the Billiton company made plans for tin mining after the war, and a number of shipyards each deemed themselves incapable to build the required vessels on their own after the war. The partnership consisted of 6 small companies which were all strong players in dredging, but wanted to be more efficient. In sales e.g. it was very inefficient for all these relatively small companies to have their own agents abroad. The partnership consisted of:

Already in July 1945, an order for 6 tin bucket dredgers came in from the Billiton Company. The order would be built by a consortium of Gusto, Conrad, Stork Hijs and Verschure & Co. under leadership of J. & K. Smit. In December 1946 IHC contracted with Turkey for 6 twin screw passenger ships. In September 1947 IHC got a French order for five big dredgers.

In the 1950s IHC contracted for many dredging vessels. In 1952 it also contracted for 5 reefer ships. In this order, Verschure & Co. and De Klop each built two ships, and J. & K. Smit only one. The engines would be built by Werkspoor and De Schelde. In 1956 IHC got an order for a cutting suction dredger to dig for bauxite in Suriname. The floating sheerleg Simson is now in the Maritime Museum Rotterdam it was built by a combination of shipyards. De Hoop in Hardinxveld would build the pontoon. Kloos en Zn. N.V. built the superstructure, and J. & K. Smit made the steam engines, tools and other machinery.

In 1960 IHC delivered a special dredger. It was a rock breaker / spoon dredger built for the Suez Canal by J. & K. Smit. It could fix itself by using studs. It would then use a 22,500 kg digging bar to break rock formations. The 4.5 m³ spoon would then pick up the fragments.

In 1965 the boards of 5 of the 6 companies which cooperated in IHC Holland decided to merge their companies. Conrad Shipyard en Stork Hijsch N.V. could not join, because it was part of the Stork conglomerate.

In 1966 IHC Holland started to merge J. &. K. Smit and L. Smit shipyards into a partnership known as Smit Kinderdijk v.o.f. In 1971 Smit Kinderdijk became IHC Smit N.V.

The single buoy mooring was an idea by Shell. It would lead to the establishment of a daughter company called Single Buoy Mooring, the nucleus of the later SBM Offshore. Gusto shipyard started production of SBMs in the late 1950s with technical assistance by Shell. SBMs became a very successful product of Gusto in the 1960s. However, during installation the builder Gusto often had to call on operator Shell for assistance. In order to solve this Robert Smulders (from the Gusto family) founded a new IHC daughter company on 27 February 1969. SBM Inc., in Fribourg, Switzerland, would specialize in SBMs. It would do marketing and sales, delivery, training of operator staff, after sales, and ideas for new products.