Description
NSE will conduct mock trading on January 17, 2026, during which the UCC (Unique Client Code) live environment will be unavailable from 10 AM to midnight. Members must refrain from UCC modifications during this period.
Summary
NSE will conduct a mock trading session on Saturday, January 17, 2026, following previous circulars NSE/CMTR/72347, NSE/FAOP/72336, NSE/CD/72334, and NSE/SLBS/72341. During this mock trading session, the Unique Client Code (UCC) live environment will be unavailable from 10 AM until midnight on January 17, 2026. Members are advised to refrain from making any UCC modifications or uploads during this period as any changes made will not be valid for live trading and will be purged from the system.
Key Points
- Mock trading session scheduled for Saturday, January 17, 2026
- UCC live environment will be unavailable from 10 AM to midnight on January 17, 2026
- Any UCC records added or modified during the unavailability period will be invalid for live trading
- Invalid UCC records will be purged from the Exchange system by end of day on January 17, 2026
- Members must avoid any UCC modifications/uploads during the specified downtime window
- Live trading resumes on Monday, January 19, 2026
Regulatory Changes
No regulatory changes introduced. This is an operational notice regarding mock trading procedures.
Compliance Requirements
- For All Members: Refrain from making any modifications or uploads to the UCC system between 10 AM and midnight on Saturday, January 17, 2026
- Planning Requirement: Members should complete any necessary UCC additions or modifications before 10 AM on January 17, 2026, or wait until after midnight on January 17, 2026
- Record Keeping: Be aware that any UCC changes attempted during the downtime will not be reflected in the live system for Monday’s trading session
Important Dates
- January 16, 2026: Circular issued
- January 17, 2026, 10 AM - Midnight: UCC live environment unavailable due to mock trading session
- January 17, 2026, End of Day: Purging of invalid UCC records created during downtime
- January 19, 2026 (Monday): Live trading resumes with valid UCC data
Impact Assessment
Operational Impact: Medium. The UCC system unavailability affects members’ ability to onboard new clients or modify existing client codes during the specified window on Saturday. However, the impact is limited as it occurs on a weekend day when trading volumes are typically lower.
Member Impact: Members need to plan UCC-related activities around the downtime window. Any urgent client onboarding requirements should be completed before 10 AM on January 17 or postponed until after midnight.
Market Impact: Low. The mock trading session is a routine exercise for system testing and does not affect actual market trading. Live trading operations resume normally on Monday, January 19, 2026.
Risk Mitigation: The Exchange has provided advance notice and clear instructions to prevent members from losing UCC data during the mock trading period. The automatic purging mechanism ensures system integrity for live trading resumption.
Impact Justification
Mock trading session requires UCC system downtime affecting member operations for one day. Members unable to add/modify UCCs during the specified period, but impact is limited to Saturday with no effect on Monday's live trading.