On Tuesday, the Swiss financial market infrastructure operator SIX outlined how the revised rules for stock and bond indices will affect its existing index families and when these changes will be implemented.

In July, SIX announced that it would move away from using the Industrial Classification Benchmark (ICB) for sector allocation and instead adopt a proprietary logic. This shift impacts the sector indices of the Swiss Performance Index (SPI), the broad market barometer for exchange-listed stocks, and the Swiss Bond Index (SBI), the equivalent for bonds, as reported by finews.ch

Equity Indices in October, Bonds on November 11th

SIX explained that the changes align with current market standards and aim to ensure that index data best reflect the evolving economic realities of financial markets. The changes are scheduled to be implemented between October and December.

The rollout will begin with adjustments to equity indices on October 21, followed by bond indices on November 11th. Additionally, four documents  detailing the categories and definitions of the new taxonomy have been published. These documents provide comprehensive information on the specific impacts of the new rules, including which sector indices will be adjusted and which new ones will be created. The old SPI sector indices will continue to be calculated until the end of the year.

New Bond Indices Launched Later

In the bond sector, however, the new indices will be introduced at a later date. This delay allows market participants to accurately reflect the bond universe under the new taxonomy, according to SIX.

While these adjustments to SPI and SBI sector indices may seem technical, the practical impacts are considerable. Many financial industry players use sector indices as benchmarks for portfolio performance or rely on such index data for back-office processes.