The Act of 1709 was an Act of Tynwald passed to regulate the currency of the Isle of Man. It addressed the scarcity of small coinage that had resulted from the growth of trade following the Act of Settlement of 1704, ordering that the copper pence and halfpence coined by Earl James should be current and passable within the Island, and imposing severe penalties for counterfeiting.

The best record of the Act at work is a case of 1723, and it did not go as the court intended. On the day the information was laid, the Deputy Governor sent men to search John Wilks's house. The searcher told George Wilks he had authority to search him on suspicion touching the counterfeit pence, and Wilks said he was at liberty to do so, but the officer, watching him, judged he had a coin about him and on a close search found a counterfeit penny hidden in the back of his breeches. Wilks admitted he had run it himself, both then and openly in court afterwards, saying he had done it to try his flasks and see how they would cast, and to try the metal. The pot for running metal, the flask or mould, and a piece of copper were taken up at the house, and he was committed to close prison.

The jury would not convict. Three of John Wilks's apprentices, Thomas Taubman, David Curlett and John Wattleworth, swore they knew nothing of the making of the pence though they usually worked with Wilks and his father. On 21 May 1723 the jury of indictment acquitted the accused, signing their verdict with their marks. A second body of jurors said they would rather impute that verdict to misunderstanding than to wilful error, and recommended the first jury to the court to be favourably used in their fine and punishment. At the Debt Court on 10 October 1723 the court fined the Grand Jury twenty shillings apiece and declared them incapable of serving on any jury or inquest in future. The Governor afterwards heard their petition, reduced the fines and restored them, holding that their error came of ignorance and a misunderstanding of the law.