Namely when the owner of natural gas infrastructure (such as an LNG regasification terminal) does not have to offer capacity to third parties, which often renders the project more attractive for the investor. This was first ratified in the Hackberry ruling in the USA. The exemption rules are nevertheless complex and include a host of additional stipulations such as possibly having to grant access to unused capacity or having to set aside a portion of the base capacity (i.e. TPA exemption can be granted but possibly only for 80% of the base capacity)