Kilner Jars were made by a Yorkshire firm of glass bottlemakers called Kilner, who operated from 1842 when John Kilner founded the first company until 1937 when they went bankrupt. At the bankruptcy sale in 1937 the patent rights to the "Kilner Jar" were bought by United Glass Bottle company and also the rights to the very similar "Mason" jar that had been made by Kilner. They went on making the Kilner and Mason jars.
The various names of the Kilner companies were:
John Kilner & Co, Castleford, Yorkshire, 1842-44
John Kilner & Sons, Wakefield, Yorkshire, 1847-57
Kilner Brothers Glass Co., Thornhill Lees, Yorkshire, 1857-73 also at Conisbrough, Yorkshire, 1863-1873
Kilner Brothers Ltd., Thornhill Lees, Yorksire 1873-1920 also at Conisbrough, Yorkshire, 1873-1937.
Hope this is helpful, Angela