Lufthansa's potential return to Germany's benchmark DAX index faces uncertainty following recent union strikes that triggered a sharp stock sell-off, according to Deutsche Bank research. The airline appeared positioned for re-entry through the fast entry rule just days ago, but its recent decline has placed inclusion 'in the balance,' strategists warn.

Under fast entry provisions, companies ranking 33rd or higher can join the DAX by replacing the lowest-ranking member. Deutsche Bank estimates Lufthansa currently holds the 33rd position, which would narrowly secure inclusion. However, the airline maintains only a €60 million buffer in free-float market capitalization to the 34th rank where eligibility ends. The final ranking will be determined by free-float market capitalization as of February 27.

If Lufthansa achieves fast entry, Zalando would face exclusion as the weakest current DAX member. The sector distribution would see minimal impact since both companies belong to the Consumer Discretionary sector. Deutsche Bank projects significant trading volume increases during the March 20 closing auction, with Lufthansa shares potentially seeing 10 to 12 times the daily average volume as ETFs adjust their positions.