The energy company Siemens Energy, which was only relegated from the Dax to the MDax in March, will soon return to the leading German index.
The cooking box supplier Hellofresh, which will then be found in the index of medium-sized values, has to be eliminated.
Deutsche Börse announced this late Monday evening after the index review.
The changes will come into effect on Monday, September 19.
The stock market value is the main factor determining the rise and fall of companies in the German stock market barometer.
The index provider measures this based on the proportion of freely tradable shares in the individual companies.
The volume-weighted average price in the last 20 trading days before the indices are checked is taken into account.
As expected, it was no longer enough for Hellofresh to remain in the Dax.
Since the beginning of the year, two-thirds have lost value.
After a brief phase of stabilization, the share's downward trend picked up speed again in mid-August.
Index changes are particularly important for funds that replicate indices in real terms (physically replicating ETFs).
There must then be shifted and reweighted accordingly, which can have an impact on share prices.
The Munich company has experienced turbulent times in the almost two years since it went public in autumn 2020.
In March 2021 they had already been included in the Dax.
But because the business of the Spanish wind power subsidiary Siemens Gamesa is weakening and the parent company has repeatedly spoiled the numbers and thus the course, Energy rose again from the MDax just a year later.
Now came only half a year later the direct resurgence.
And that is by no means all that Energy is currently busy with: the company is repeatedly in the headlines for turbines for the Nord Stream 1 gas pipeline.
According to Russia, the flow of gas there is blocked due to a leak in a turbine.
According to earlier information from the Russian side, papers are missing for another turbine that was serviced in Canada.
However, German government agencies and in some cases also Siemens Energy have clearly contradicted these statements.
For the time being, the assessment that the reported findings do not constitute a reason for the cessation of operations applies, said a spokesman on Monday.
"Such leaks do not normally affect the operation of a turbine and can be sealed on site." In the past, such oil leaks have not caused a standstill either.
At the same time, an attempt is being made to take over Siemens Gamesa completely and take it off the stock exchange in order to get the company back on track more easily.
So far, Energy only holds two-thirds of the subsidiary, which has significant problems in the field of onshore wind turbines.
A takeover bid for the outstanding shares worth around four billion euros was announced in May.
It is currently being routinely checked by the Spanish stock exchange regulator.