John Kay (17 June 1704 – c. 1779) was an English inventor whose most important creation was the flying shuttle, which was a key contribution to the Industrial Revolution.

[20][21] It greatly accelerated weaving,[22] by allowing the shuttle carrying the weft to be passed through the warp threads faster and over a greater width of cloth.

[26] The flying shuttle was to create a particular imbalance by doubling weaving productivity without changing the rate at which thread could be spun,[28] disrupting spinners and weavers alike.

Kay tried to promote the fly-shuttle in Bury, but could not convince the woollen manufacturers that it was sufficiently robust; he spent the next two years improving the technology, until it had several advantages over the device specified in the 1733 patent.

[31] Kay (and, initially, his partners) launched numerous patent infringement lawsuits, but if any of these cases were successful,[32] compensation was below the cost of prosecution.

Rather than capitulate, the manufacturers formed "the Shuttle Club", a syndicate which paid the costs of any member brought to court; their strategy of patent piracy and mutual indemnification nearly bankrupted Kay.

[33] In 1745, he and Joseph Stell patented a machine for cloth ribbon weaving, which they anticipated might be worked by water wheel,[19] but they were unable to advance their plans because of Kay's legal costs.

[9] Kay remained inventive; in 1746 he was working on an efficient method of salt production,[35] and designing improvements to spinning technology: but that made him unpopular among Bury spinners.

John Kay unsuccessfully tried to enforce his manufacturing monopoly, and began to quarrel with the French authorities, briefly returning to England, in 1756[46] (it is said[by whom?]

that he was in his Bury home in 1753 when it was vandalised by a mob, and that he narrowly escaped with his life,[31][47] but this is probably a 19th-century tale based on earlier Colchester riots; Kay was probably in France throughout the early 1750s).

His offer to teach pupils if the pension were restored was not taken up, and he spent his remaining years developing and building machines for cotton manufacturers in Sens and Troyes.

[52] John Kay's son, Robert, stayed in Britain,[53] and in 1760 developed the "drop-box",[19][54] which enabled looms to use multiple flying shuttles simultaneously, allowing multicolour wefts.

In 1782 he provided an account of his father's troubles to Richard Arkwright, who sought to highlight problems with patent defence in a parliamentary petition.