A plethora of different mechanisms are used to block a hostile takeover bid from abroad. Some are enshrined in national law, others are cultural or built into corporate structures. Many of the same restrictions, and new ones, are being used to prevent opportunist commercial mergers by companies which would provide an abuse of competitive position.
National laws may prevent foreign ownership of newspapers, radio and TV stations, banks and defence industries. They may also ban ownership of industries crucial to national defence. Some countries prevent companies from acquiring dominate positions in a specific market. Companies place new bond issues in friendly hands which will exercise the attached equity warrants only in the event of an unwelcomed approach. Private companies have hard cores of friendly shareholders, i.e. family members, sister companies and board members (in Italy it is families, in Germany it is banks), and many countries have restrictive share practices. Complex pyramids of holding companies, sometimes spread internationally are used to frustrate takeover attempts. Employees can discourage hostile takeovers, managers and trade unions may be opposed to any bids to protect jobs and for fear of being shamed, in the case of Japanese companies. Labour unions may lobby legislative and regulatory bodies. Some companies erect their own barriers. Swiss companies can fashion their own statutes and decide which shares they will register and thus give voting rights to.