 Over the next century , the granting of full industrial patents became a more common practice in England ; the next record is a letter from 1537 to Thomas Cromwell , Henry VIII 's private secretary , from Antonio Guidotti , a Venetian silk @-@ merchant . Guidotti had persuaded a group of Venetian silk @-@ makers to practice in England , and wanted the king to grant him letters patent protecting their monopoly to grow silk for 15 or 20 years . This was granted , and Henry 's son Edward VI followed up with a grant of letters patent to Henry Smyth , who hoped to introduce foreign glassworking techniques into England . This process continued after Elizabeth I came to the throne , with formal procedures set out in 1561 to issue letters patent to any new industry , allowing monopolies . The granting of these patents was highly popular with the monarch , both before and after the statute of Monopolies , because of the potential for raising revenue . A patentee was expected to pay heavily for the patent , and unlike a tax raise ( another method of raising Crown money ) any public unrest as a result of the patent was normally directed at the patentee , not the monarch . 
