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System Operator Transmission Owner Code (STC)
The System Operator Transmission Owner Code defines the relationship between the transmission system owners and the system operator.
As the code administrator for the STC, we maintain the code and oversee any proposed changes to it. All changes have to be reviewed by the STC modification Panel and approved by the Panel, or by Ofgem.
You can find out more about the roles and responsibilities of everyone involved in the STC procedures document, on the Code documents page.
For more information about the code, please contact stcteam@nationalgrideso.com.
You can subscribe to the STC mailing list here.
Latest STC Updates
Modification Tracker
6 January 2020
Our Modification Tracker gives you the very latest detail on current modifications for each of the four codes. It includes the purpose of the modification and the stakeholders it affects, as well as Panel comments on prioritisation, and where it is in the review process.
This Modification Tracker will be published on a monthly basis on the 7th calendar day of the month or the next working day where the 7th is a non-working day.
Standing Groups
21 June 2017
Standing groups give interested industry people the opportunity to discuss issues relating to electricity codes in more detail. Issues could relate to one or more of the codes, including the STC.