 The Statute of Monopolies was an Act of the Parliament of England notable as the first statutory expression of English patent law . Patents evolved from letters patent , issued by the monarch to grant monopolies over particular industries to skilled individuals with new techniques . Originally intended to strengthen England 's economy by making it self @-@ sufficient and promoting new industries , the system gradually became seen as a way to raise money ( through charging patent @-@ holders ) without having to incur the public unpopularity of a tax . Elizabeth I particularly was a great abuser of the system , issuing patents for common commodities such as starch and salt . Unrest eventually persuaded her to turn the administration of patents over to the common law courts , but her successor , James I , was even more abusive . Despite a committee established to investigate grievances and excesses , Parliament made several efforts to further curtail the monarch 's power . The result was the Statute of Monopolies , passed on 25 May 1624 . 
