A company will sometimes engage in a defensive acquisition strategy by purchasing smaller firms that are in the same business. By acquiring these firms, the company protects itself from takeovers from other companies, which, as a result of antitrust laws, may not be able to merge with the enlarged company without creating a monopoly.
If a North American car company acquired an SUV company as a result of the projected rise in demand for SUVs, this would be an example of a defensive strategy through the purchase of assets.