Community Submission - Author: Tanwa Arpornthip
An asset is considered fungible when its units are interchangeable with one another, meaning they are indistinguishable. In other words, an asset class is fungible when each unit of the asset has the same validity and market value. For example, a pound of pure gold is equal to any other pound of pure gold, regardless of the shape. Other examples of fungible asset classes may include commodities, fiat currencies, bonds, precious metals, and cryptocurrencies.
However, an equal exchange of a fungible asset does not necessarily mean exchanging of two identical units. As long as the transaction happens between instruments of the same kind and that share the same functionality, it can be considered as an equal exchange. For instance, a five-dollar bill can be exchanged with five one-dollar bills, but they have the same validity. In this example, the US dollar is the fungible asset, while the bills merely represent their underlying value.
In general, most cryptocurrencies are considered fungible assets. For example, we may consider Bitcoin fungible because each unit of BTC is equivalent to any other unit, meaning they have the same quality and functionality. So it doesn’t really matter in which block the coins were issued (mined), all Bitcoin units are part of the same blockchain and have the same functionality. Note that if someone forks the blockchain and create a new Bitcoin, those coins won’t be considered original as they would be part of another network.
It has been pointed out that due to the inherent traceability of BTC and similar cryptocurrencies, some coins might be less desirable than others - especially if they have been previously used in dubious or illicit activities. This means that some merchants or service provides may deny receiving Bitcoins as payments if they believe those particular coins were used by criminals in the past.
Unlike some tend to believe, however, this fact doesn’t remove Bitcoin’s property of fungibility. Traceability and fungibility are two different things and, despite their transactional history, each Bitcoin is still the same in terms of quality, technology, and functionality. Similarly, the US dollar is still a fungible asset, although criminals have been using it for illicit activities for many decades.