Frankfurt (dpa) – French-German aeroplane maker Airbus, sports apparel company Puma and medical technology firm Siemens Healthineers are among the 10 companies to be added to the DAX, Germany’s main stock exchange index, later this month, the bourse announced on Friday.

The move to expand the Dax from 30 to 40 companies comes amid a series of other changes designed to “increase the quality” of the DAX – such as tighter reporting requirements and tougher requirements for achieving profits – that were pushed through in the wake of the Wirecard scandal.

Wirecard was a payments firm that went bankrupt about a year ago after the company admitted it could not account for much of the money it was supposed to have. However, DAX rules at the time required Wirecard to stay on the market, even as its worth and stock value vanished.

Many of the proposals mooted had been discussed since November. The move to 40 companies will take effect on September 20.

Along with Airbus, Puma and Siemens Healthineers, the DAX will also welcome: chemical trader Brenntag; food delivery company Hellofresh; the Porsche holding company; biotechnology and diagnostics firm Qiagen; pharmacy and laboratory provider Satorius; aroma and scent maker Symrise; and online clothing retailer Zalando.

While the DAX gets bigger, the MDAX market of medium-sized companies will shrink from 60 to 50.

The new rules require members of the DAX to have profits in the two most recent quarters starting in December and, as of March will have to produce regular annual and quarterly statements. Twice-a-year reviews of the firms will begin this year, as opposed to the once-a-year system in place now.

“Market participants will benefit from a simple set of rules in line with international standards and new qualification criteria for the German benchmark index, which tracks the largest listed companies on the German capital market,” said Stephan Flaegel, global head of benchmarks and indices at Qontigo, a financial intelligence firm that is part of the Deutsche Boerse group.