Germany’s Volkswagen has signed a deal to buy the other half of Porsche’s car manufacturing operations that it does not already own for €4.46 billion, completing a takeover effort nearly three years in the making.

The two car makers said they had finalised plans to speed up the formation of a merged group that will see Porsche’s 911 sports car join a VW empire that combines luxury Bentley and Bugatti cars, budget brand Skoda and the MAN and Scania truck makers.

The integration is due to take place from August 1, with VW set to pay Porsche’s holding company €4.46 billion ($5.59 billion) in cash, plus one ordinary share in Volkswagen, in exchange for the remaining 50.1% of the sports-car operations. The companies also said the quicker than expected integration would generate €320m in net synergies.

Volkswagen bought an initial 49.9% stake in Porsche in late 2009 in the first stage of the complex takeover agreement but it has since remained in limbo.

Porsche’s takeover attempt nearly bankrupted the company, triggering lawsuits running to billions of euros from angry investors who claim that Porsche misled the market. Porsche has always rejected the accusations.