By Victoria Waldersee

BERLIN, (Reuters) –Volkswagen AG is now part of Porsche SE, and they have reached a framework agreement in preparation for an IPO, said the companies on Tuesday. This was the first time that the parties had confirmed the possibility of a Porsche AG listing.

Volkswagen (DE), stated that the final decision has not been made yet and that the agreement must be approved both by the supervisory and management boards.

These statements opened the door to what may be one of the most important ever European listings. Reports estimate that the luxury carmaker could have a value of between 45 and 90 billion euros (51 billion-$102 billion).

Volkswagen claimed that “whether a Framework Agreement…is concluded…is currently open” and it depends on approval by both the boards.

Porsche SE indicated that the transaction could involve the acquisition of ordinary shares which, in turn, confer voting rights to the holder.

After a small drop in early trading, both Volkswagen SE shares and Porsche SE share gained 10% each to 192.48 euro and 88.8 euro respectively.

The stock market has seen speculation about Porsche’s listing rise several times in the last year, but due to the complex stakeholder setup no decision was made.

Sources revealed to Reuters that last year, the Porsche family and Piech families owned 31.4% Volkswagen shares and had 53.3% of the voting rights via Porsche SE. This led them to consider buying a stake in Porsche AG.

A similar move could allow families to let go of Volkswagen and take over direct ownership. This is the Porsche brand that their grandfather Ferdinand founded in 1931.

($1 = 0.8827 euros)