Schaeffler’s audacious bid for Continental, the tyre and car-parts group, sparked political debate on Thursday on Germany’s takeover law amid a global crackdown on the disclosure of derivatives.

Politicians of both the CDU and SPD, the ruling parties, said they would consider tightening rules for the notification of equity derivatives after Schaeffler, a privately-owned ball-bearings group, secretly built a 36 per cent stake in Conti.