German logistics entrepreneur Klaus-Michael Kuehne has increased his stake in Lufthansa to 15% from 10%, Lufthansa said late on Wednesday, making him the biggest shareholder in the German flag carrier.
The news pushed shares in the airline 2.4% higher at market open on Thursday. At Wednesday's closing price, 5% of shares in Lufthansa were worth around 330 million euros ($337 million).
Kuehne had most recently boosted his stake in Lufthansa to 10% in April. The German government holds around 14% of Lufthansa via its Economic Stabilisation Fund.
Kuehne has said in the past that he aimed to be a long-term, stable and reliable partner for Lufthansa.
The German billionaire is also the controlling shareholder of Swiss logistics firm Kuehne & Nagel and has a 30% stake in container shipping company Hapag-Lloyd AG.