An intangible asset is an asset that lacks physical substance. Examples are patents, copyright, franchises, goodwill, trademarks, and trade names, as well as software. This is in contrast to physical assets (machinery, buildings, etc.) and financial assets (government securities, etc.). An intangible asset is usually very difficult to valuate. They suffer from typical market failures of non-rivalry and non-excludability. Today, a large part of the corporate economy (NPV) consists of intangible assets.