The current Internet Protocol (IP) addressing system, Internet Protocol version 4 (IPv4), is a resource with limitations. All IPv4 address blocks have now been allocated, posing a risk that not all IP address requests will be satisfied. As IP addresses may be considered public goods, it is important that they are allocated efficiently in order to comply in an equitable manner with the demands of all Internet participants. At the moment it is uncertain as to when, or even whether, Internet Protocol version 6 (IPv6) will replace IPv4. This article looks at the current system of IP address allocation and the risks and benefits of introducing an IP address transfer market in compliance with constitutional principles.