On Jun. 16, 2025, OSX issued a summary of comments received and its responses.
Given that the current DCB price ranges are uniformly set on a tick basis, the new DCB price ranges will be adjusted according to the relevant DCB reference price level.
Reassured that revisions will contribute to enhancing the price discovery function.
OSX will improve the convenience of the derivatives market by reviewing trading rules, taking other actions in light of market conditions and the needs of market participants.
Revised Business regulations and Enforcement rules will be valid from Nov. 17, 2025.
JPN EXC proposed revisions to option trading rules including tick sizes for Nikkei 225 options and Nikkei 225 mini options, as well as immediately executable price ranges.
Outline of Revisions
Revise the tick size for Nikkei 225 options and Nikkei 225 mini options to JPY 1 for premiums of JPY 300 or less and to JPY 5 for premiums of greater than JPY 300.
Revise immediately executable price ranges (DCB price ranges) for index options trading depending on the level of the DCB reference price, instead of ±10 ticks.
Set DCB price ranges for securities options depending on the level of DCB reference price, instead of the base price of price limits on orders for underlying securities.
Consultation Period
Comments shall be submitted by Apr. 26 for planned effectiveness from Aug. 18, 2025.
Jun. 2025 Revisions Finalized
On Jun. 16, 2025, OSX issued a summary of comments received and its responses.
Given that the current DCB price ranges are uniformly set on a tick basis, the new DCB price ranges will be adjusted according to the relevant DCB reference price level.
Reassured that revisions will contribute to enhancing the price discovery function.
OSX will improve the convenience of the derivatives market by reviewing trading rules, taking other actions in light of market conditions and the needs of market participants.
Revised Business regulations and Enforcement rules will be valid from Nov. 17, 2025.
