Rolled Steel Products Holdings Limited v British Steel Corporation & Others

A transaction is only ultra vires (and void) if it falls outside the company's capacity as defined by the objects in its memorandum; an act within the company's capacity but done for an improper purpose or in breach of directors' duties is intra vires but an abuse of power, and binds the company unless the counterparty had actual or constructive notice of the impropriety or want of authority.