Delays to the A380 hammered the EADS share price
France's stock market regulator said it has uncovered evidence of insider trading and market abuse at Airbus parent firm EADS.
The findings follow an 18-month AMF probe into whether managers at the firm were aware of problems affecting its A380 planes before they sold shares.
When details of delays to the superjumbo project were announced in June 2006, shares in EADS slumped.
EADS said that it would "exercise vigorously" its right to defend itself.
"EADS will support its managers in their defence, it intends to demonstrate that it has applied standards of excellence when communicating to the market and has acted with full transparency."
However it accepted that the proceedings may have "significant consequences on its image and reputation".
And one of its key shareholders, Lagardere, said that it was "confident of its ability to provide all explanations needed to clear it".
The regulator will now refer the case to Paris prosecutors.
It added that despite its findings no one had yet been found guilty of any illegal activity.
The trading in shares occurred shortly before news about delays to the A380 superjumbo were made public last June.
EADS denies it knew about delays when millions of euros of shares were sold.
The announcement wiped 26% off the value of the Franco-German aerospace giant.