Vienna prosecutors have named Airbus chief executive Tom Enders as one of the targets of a fraud investigation.
The dispute stems from Austria's 2 billion-euro (£1.7bn) Eurofighter warplane purchase more than a decade ago.
Its defence ministry has said it was misled over the pricing.
Airbus confirmed that Mr Enders is a subject of the inquiry, adding that the allegations are "completely unsubstantiated."
Austria said in February it would sue French aerospace giant Airbus and the Eurofighter consortium, citing money related to local contracts they said was hidden in the cost of the planes.
Airbus said on Wednesday: "Upon our inquiry after initial media reports, the Vienna prosecutor this afternoon informed us for the first time that all individuals, who have been mentioned by the Republic of Austria in its statement of alleged facts... are under investigation," an Airbus spokesman said.
"This list of individuals includes, among others, Tom Enders. As we have repeatedly stated, we consider the accusations as completely unsubstantiated."
The Eurofighter consortium, which comprises BAE Systems, Italy's Leonardo and Airbus, has also denied any wrongdoing.