Takeover law is still evolving in continental Europe, as individual countries slowly fall in line with requirements mandated by the European Commission. Stakebuilding is commonplace in many continental takeover battles such as Scania AB. Formal poison pills are quite rare in continental Europe, but national governments hold golden shares in many "strategic" companies such as telecom monopolies and energy companies. Governments have also served as "poison pills" by threatening potential suitors with negative regulatory developments if they pursue the takeover. Examples of this include Spain's adoption of new rules for the ownership of energy companies after E.ON of Germany made a hostile bid for Endesa and France's threats to punish any potential acquiror of Groupe Danone.