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 Market Rules 

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 The Market Rules consist of the latest approved Trading and Settlement Code, Agreed Procedures and any 'approved' Modifications which have not yet been incorporated into the main body of the Code or the Agreed Procedures (see Approved Modifications at the Modification Proposals page).

It is important to note: a Modification may become effective before the published draft of the Code is amended to include the Modification. Please see Modification Proposals currently in effect on the baseline below.

Part A of the Trading and Settlement Code is available below. 

Part B and Part C of the Trading and Settlement Code are available in the Regulatory Affairs section of General Publications. 


  Mod Id Modification Title Effective Date
 MOD_31_18Imbalance Pricing During Outages of the Imbalance Pricing System27th Sep 2018
 MOD_30_18Market Back Up Price Ammendment27th Sep 2018
 MOD_29_18Part B Schedule Production Cost Definition27th Sep 2018
 MOD_28_18Ordering of Pseudo Dispatch Instructions for QBOA with the same Instruction Issue Time and Instruction Effective Time27th Sep 2018
 MOD_26_18Market Back Up Price Reference Corrections27th Sep 2018
 MOD_24_18Use of Technical Offer Data in Instruction Profiling / QBOA27th Sep 2018
 MOD_22_18Part B Credit Cover Signage & Subscript Correction27th Sep 2018
 MOD_21_18Application of Settlement Reallocation Agreements to Market Operator Charges & Settlement Dcument Definition & Usage27th Sep 2018
 MOD_20_18Agreed Procedure Updates27th Sep 2018
 MOD_19_18Part B Housekeeping 127th Sep 2018
 MOD_17_18Mod_17_18 Transitional Provisions for Cutover27th Sep 2018
 MOD_16_18Mod_16_18 Interim Suspension Delay Periods27th Aug 2018
 MOD_15_18Mod_15_18 Clarifications for Instruction Profiling27th Aug 2018
 MOD_14_18Mod_14_18 Change to timing of publication of Trading Day Exchange Rate27th Aug 2018
 MOD_13_18Mod_13_18 Calculating Obligated Capacity Quantities for Units Not Yet Commissioned27th Aug 2018
 MOD_11_18Mod_11_18 Correction of Minor Material Drafting Errors20th Jun 2018
 MOD_10_18Mod_10_18 Amendment to Capacity Settlement Publication from Monthly to Daily20th Jun 2018
 MOD_09_18Mod_09_18 Interim Credit Treatment for Participants with Trading Site Supply Units27th Aug 2018
 MOD_08_18Mod_08_18 Clarification of rules used to determine the value of Price Average Reference Tag (TPAR)21st Jun 2018
 MOD_07_18Mod_07_18 Clarifications of use of variable “b” in NIV and PAR Tagging scenarios27th Aug 2018
 MOD_06_18Mod_06_18 - Clarification of Marginal Energy Action Price calculation including scenario when all actions are flagged21st Jun 2018
 MOD_05_18Mod_05_18 Clarification of Administered Scarcity Pricing function for scenarios not yet covered in rules20th Jun 2018
 MOD_04_18Mod_04_18 Reporting and Publication for Operational Schedules, Dispatch Instructions, Forecast Availability and SO Trades20th Jun 2018
 MOD_01_18Notification of Suspension to SEM NEMOs5th Apr 2018
 MOD_18_17Net Inter Jurisdictional Flow Submission27th Sep 2018
 MOD_17_17Recovery of Costs due to Invalid Ex-Ante Contracted Quantities in Imbalance Settlement20th Apr 2018
 MOD_16_17Funding in relation to EirGrid/SONI payment obligations20th Apr 2018
 MOD_15_17Credit Treatment for Adjusted Participants29th Mar 2018
 MOD_14_17Part B Suspension When Suspended Under Part A29th Mar 2018
 MOD_13_17Deferral of SEM NEMO Credit Reports and Non-acceptance of Contracted Quantities27th Aug 2018
 MOD_12_17Outage Adjusted Wind and Solar Forecast Reports29th Mar 2018
 MOD_11_17Deferral of Information Imbalance Charges9th Feb 2018
 MOD_10_17Ex-Ante Quantities Deferral26th Feb 2018
 MOD_09_17Solar in I-SEM6th Feb 2018
 MOD_08_17Decremental Price Quantity Pair Submission6th Feb 2018
 MOD_07_17Credit Assessment Volume for Generator Units6th Feb 2018
 MOD_06_17Transitional Credit Cover Provisions26th Feb 2018
 MOD_05_17Amendment to the Part B Form of Authority for the purpose of removing the Restricted Authority provision24th Oct 2017
 MOD_04_17Solar in the SEM24th Oct 2017
 MOD_03_17Treatment of Transmission Losses for Trading Sites with Contiguous Autoproducers in I-SEM19th Oct 2017
 MOD_02_17Unsecured Bad Energy Debt & Unsecured Bad Capacity Debt Timelines.27th Sep 2018

SEMO is a joint venture between EirGrid PLC and SONI Limited