The Blancos have opposed the CVC proposal since it was announced in early August and are now stepping up efforts to get it torn up
Real Madrid have opened legal proceedings against La Liga president Javier Tebas and CVC's €2.7 billion (£2.3bn/$3.2bn) investment deal in the Spanish top flight.
It was announced on August 4 that a private equity firm had acquired a 10 per cent stake in one of world football's biggest brands.
Opposition to that agreement came from the very top, as Real and Clasico rivals Barcelona questioned the legality of it, and the Blancos have now taken matters a step further.