Typically, the exchange of substituents between two olefins in the presence of a catalyst to form two new olefins is called an olefin metathesis reaction. The application of the olefin metathesis reaction to synthesize polymers is called olefin metathesis polymerization. The most commonly used catalyst for olefin metathesis polymerization is the ruthenium‐based Grubbs catalyst, consisting of a carbon–metal double bond. For simplicity, the catalyst is often represented as shown where M is the metal with its ligands. Generally, olefin metathesis polymerization occurs in two ways: ring-opening metathesis polymerization or ROMP and acyclic diene metathesis or ADMET. Both of these methods have the advantage of being compatible with olefin monomers over various other functional groups. The commercially available polymers synthesized by the olefin metathesis polymerization include Vestenamer, used for manufacturing rubber objects, and Norsorex, used as a superabsorbent polymer for oil.