Trading parties can raise a dispute if they believe another party in the market is operating incorrectly in relation to; incorrect data items, inaccuracy of settlement reports, non-adherence to the Market Arrangements Code (MAC) obligations and/or non-adherence to other areas of the code.

You can find out more about the different types of disputes below, along with a list of all active disputes.

Trading Disputes

Trading Disputes occur when two trading parties disagree on whether a data item has been accurately maintained, which has had an effect on Primary Charges. Under the Market Arrangements Code (MAC), parties have an obligation to ensure that data is maintained accurately. In the event of inaccuracy, raising a Trading Dispute effectively escalates the dispute to ensure rectification. Prior to raising a Trading Dispute, however, a trading party must make all reasonable steps to resolve the discrepancy with the parties involved.

For more information, please visit the Trading Disputes page.

Market Operator (MO) Disputes

The Market Operator (MO) Dispute resolution process aims to rectify any errors considered to be the cause of inaccurate results occurring within the Settlement Report. An error can be raised by the contracting wholesaler or retailer, but must not be due to errors in or omissions of any data items, as this would constitute a Trading Dispute.

For more information, please visit the MO Disputes page.

MAC and Non-Trading Disputes

MAC Dispute resolution is designed to resolve any issue, in which a trading party believes an organisation, either MOSL or another trading party, has failed to comply in accordance with their obligations, as stipulated in the market codes. A Non-Trading Dispute follows the same procedure as that contained within the MAC Dispute. The dispute will have the same process, but will differ in terms of the scope.

For more information, please visit the MAC and Non-Trading Disputes page.

Disputes List

Please find the list of all open disputes below.

Dispute type Publication date Title Description
Unified 26/03/2021 DIS0032 Castle Water Limited (Castle) asserts that Thames Water Limited (Thames) have not used Visual reads when submitting Final reads in the case of 417 SPIDs . This is contrary to Section 3.3.3 of CSD0202 Meter Read Submission: Process - “The only permitted Meter Read Method for a Final Read is “Visual”.
Unified 20/11/2020 DIS0021 Thames Water state that Castle Water are incorrectly withholding settlement charges relating to SPIDs where Castle Water state that Thames Water as a Wholesaler have a responsibility to provide remote reading systems.
Non Trading 06/05/2020 COD00060 Marston’s PLC has raised a dispute with Severn Trent Water in relation to Wholesale Retail Code: Business Terms – Schedule 3: Alternative Eligible Credit Support. The parties are yet to agree on a resolution and the dispute remains open.
MAC 19/11/2018 COD00054 Thames Water provided Castle Water with a list of supply points, where an issue has been identified concerning to defective meter pit covers. As a result, meter reads were unable to be taken.
MAC 19/11/2018 COD00053 A list of supply points held by Thames Water have been identified by Castle Water as having meters located in an unsafe location and subsequently meter reads were unable to be taken.
MAC 19/11/2018 COD00051 A list of supply points held by Thames Water have been identified by Castle Water as having an issue related to damaged meters. As such, meter reads are unable to be input.
MAC 19/11/2018 COD00049 Castle Water has identified a number of supply points held by Thames Water with meters associated with defective reading systems. As such, meter reads are unable to be input.


Disputes Committee

View the latest information from the Disputes Committee.


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