The book examines the civil law protection options available to shareholders and the target company in cases of defective offering documents within the framework of securities acquisition and takeover procedures. The background is the significant limitation imposed by the II Senate of the Federal Court of Justice regarding the legal protection enjoyed by the recipient of a public offer for the acquisition of publicly listed securities of a target company. As a thorough exploration of this inadequately addressed topic in the literature is urgently needed, the author comprehensively analyzes the legal protection system of the Securities Acquisition and Takeover Act (WpÜG) and places it in the context of the claim system of the German Civil Code (BGB). This includes not only the legal options available to the shareholders of the target company but also to the company itself.