3. c. 19) was an act of the Parliament of the United Kingdom of Great Britain and Ireland that made it illegal to hold a meeting of more than 50 people.

In the latter case, the organizers were required at least five days prior to the meeting to either publicly advertise in a newspaper the time, place and purpose the event, or submit a notice to a clerk of the peace.

[7] The act also established regulations for places where lectures or debates were held, requiring these to be licensed and allowing officials to inspect them.

[8] The legislation also suppressed secret societies and clubs, banning any such organization whose members were required to take an oath not authorized by law.

Parliament had become concerned with a perceived rise in radical activities by groups such as the Hampden Clubs and the Spencean Philanthropists, and several recent incidents, such as the Spa Fields riots of December 1816, an attack on the Prince Regent in January 1817, and the march of the Blanketeers that March, prompted the enactment of the Act.