Investable Weight Factor Maintenance Rebalancing Frequency Investable Weight Factors (IWFs) are reviewed annually based on the most recently available data filed with various regulators and exchanges. For the S&P Dow Jones indices, updated IWFs resulting from the annual review are applied either prior to the open of the Monday after the third Friday of September or a date that is more appropriate for a particular index family. For example, the S&P Global BMI constituents’ new IWFs are applied at the annual reconstitution at the open of the Monday after the third Friday of September; for the S&P Frontier BMI index constituents, revised IWFs are applied at the annual reconstitution at the open of the Monday after the third Friday of March. Please refer to individual index methodologies for specifics on IWF rebalancing schedules.
Timing of Changes
Annual Review:
IWF changes are implemented based on the latest publicly available share and ownership information. All IWFs of 0.96 or above are rounded to 1.00 at the annual review.
Quarterly Review:
IWF changes are implemented if the change is at least 5% of total shares outstanding and is related to a single corporate action, regardless if there is an associated share change. For quarterly reviews that coincide with the annual review, the annual review rules apply.
Mandatory Actions:
In order to minimize index turnover, any IWF changes resulting from M&A activity are implemented based on the pre-event IWFs of the securities involved.
Non-Mandatory Actions:
- For actions qualifying for accelerated implementation, IWF changes are implemented to help mimic the shares made available in the offering.
- For actions of at least US $1 billion that qualify for accelerated implementation, IWF changes are implemented to reflect the shares made available in the offering plus the latest share and ownership information publicly available at the time of the announcement.