DAX is a trademark of ISS STOXX Index GmbH, which belongs to Deutsche Börse Group. The DAX index is both a barometer for the German economy and a benchmark for a large number of financial products. As a selection index, it tracks the largest companies listed on the Frankfurt Stock Exchange. In addition to the DAX itself, the DAX index family comprises further indices such as the MDAX^®, which tracks the 50 largest companies that follow DAX, the SDAX^® index, with the 70 next biggest companies after the MDAX index, and TecDAX^®, with a focus on technology companies.

The indices are reviewed on the third trading day of the review month. Changes take effect on the Monday after the third Friday in the review month.

Companies qualify for admission to the DAX index based on the following main criteria:

• Free float market capitalisation on a specific date (last trading day of a month) - this figure is calculated using the volume-weighted average price (VWAP) of the last 20 trading days

STOXX publishes its monthly “equity index rankings”, which serve as a basis for decision-making in index reviews. For a company to be included in a ranking list:

• an existing listing on the Regulated Market of the FWB® Frankfurt Stock Exchange
• shares must have a minimum free float of ten percent
• it must have its legal headquarters or operating headquarters in Germany
• must have positive EBITDA for the two most recent fiscal years to be included in the DAX 
• continuously trade on Xetra
• must have a minimum period since first listing: at least 30 trading days
• must submit annual financial statements, half-yearly reports and quarterly figures
• it must adhere to certain provisions relating to audit committees in the German corporate governance Code.

Foreign companies may be admitted to the DAX if they have their legal headquarter in a EU or EFTA country, or an operating headquarter in Germany.

DAX is subject to regular reviews in March and September. All indices are also subject to a quarterly basis based on the “Fast Entry” and “Fast Exit” rules, with higher inclusion and exclusion hurdles than for the regular reviews. These index adjustments are intended to take into account significant changes on the ranking list. These may arise, for example due to companies that no longer have the necessary size (free float market capitalization), for example due to large changes in the free float or large drops in price.

Overview of rules for index composition:

• Fast-Exit:
  A company is excluded from the index if it has a rank worse than 60 in DAX, 110 in MDAX, 180 in SDAX, and 45 in TecDAX for the criteria of free float market capitalisation. It is replaced by the company with a rank equal or better than 47 in DAX, 97 in MDAX, 167 in SDAX, and 35 in TecDAX for both criteria.
• Fast-Entry:
  A company is included in the index if it has a rank equal or better than 33 in DAX, 83 in MDAX, 153 in SDAX and 25 in TecDAX for the criteria of free float market capitalisation. The company that is removed from the index will have a rank worse than 47 in DAX, 97 in MDAX, 167 in SDAX and 35 in TecDAX.
• Regular-Exit:
  A company can be excluded from the index if it has a rank worse than 53 in DAX, 103 in MDAX, 173 in SDAX, and 40 in TecDAX, provided that there is a company that has a rank equal or better than 47 in DAX, 97 in MDAX, 167 in SDAX and 35 TecDAX for both criteria. If no alternate candidate can be determined, there is no change.
• Regular-Entry:
  A company can be included in the index if it has a rank equal or better than 40 in DAX, 90 in MDAX, 160 in SDAX and 30 in TecDAX for both criteria, provided that there is a company that has a rank worse than 47 in DAX, 97 in MDAX, 167 in SDAX and 35 in TecDAX. If no alternate candidate can be determined, there is no change.

Resulting adjustments to the indices are announced quarterly in March, June, September and December; however, the indices with their new composition are not calculated until the rebalancing dates around two weeks after announcement of adjustments. More precisely, the indices are rebalanced on the Monday following the third Friday in March, June, September and December, as the DAX futures expire on those particular Fridays. This ensures that new index composition is also reflected in the DAX futures, enabling market participants to prepare for impending changes and adjust their portfolios as necessary. The new composition not only involves adding new companies to the index but also updating relevant key figures in the indices on a quarterly basis and limiting the weighting to a maximum of ten percent to prevent heavyweights from dominating.

If a company becomes insolvent, is taken over by another company or its free float drops to below ten percent, an extraordinary replacement may also be undertaken before the set dates.