On 12 September 2003, NECA granted WMC (Olympic Dam Corporation) Pty Limited an exemption from the requirement to register as a network service provider and the operation of Chapter 5 of the National Electricity Code. The exemption was granted under clause 2.5.1 of the National Electricity Code in accordance with NECA's NSP Registration Exemption Guidelines, and is subject to the following conditions:
- WMC will ensure that connected users will have the opportunity to purchase electricity from a retailer of their choice;
- WMC will take no action which prevents a retailer from selling electricity to any of the connected users;
- WMC will allow access to their network on reasonable commercial terms to be negotiated with each party seeking access;
- To the extent that charges are not dealt with under the Indenture granted under the South Australian Roxby Downs (Indenture Ratification) Act 1982, WMC will apply charges to users of the WMC network determined in accordance with such mechanisms imposed by the ACCC or ESCOSA, as appropriate, as are considered necessary to ensure the proposed charges are fair and reasonable;
- WMC will notify NECA and ESCOSA if a third party seeks access either to its 275kV or its 132kV network assets; and
- WMC will allow all users access to a dispute resolution mechanism.
After 27 July 2016, this exemption was registered by BHP Billiton Olympic Dam Corporation Pty Ltd / ABN 99 007 835 761