Anne it is odd that article implies Johnathon (sic) was still alive in 1863 - it might have been taken from Grace's guide (see below).
Perhaps some assumptions have been made down the line?
You have discovered that
'Jonathan died 1857 in Kingswinford aged 50, burial date 06 May 1857'Grace's guide is
implying here that Jonathon was still alive in 1863 as well
http://www.gracesguide.co.uk/Hodgetts,_Richardson_and_Pargeter'Hodgetts, Richardson and Pargeter
Hodgetts, Richardson and Pargeter, of Wordsley Glass Works, Stourbridge
1854 Benjamin Richardson and his brother Jonathan went into partnership with their nephews, Philip Pargeter and William James Hodgetts.
1863 John Thomas Haden Richardson left Richardsons to join the Tutbury Glass Co as a managing partner.
Benjamin and Jonathan between them had lost their three oldest sons to other companies. So they turned to their nephews, Philip Pargeter and William James Hodgetts Parageter who returned to the firm.
1863 the two nephews with their Richardson
uncles formed a new partnership of Hodgetts, Richardson and Pargeter.
5 designs registered from 1865 to 1870
1869 the partnership was dissolved. Pargeter remained for two more years as the Manager.
1871 Philip Pargeter left to take over the Red House Glassworks. Benjamin Richardson talked his son Henry Gething Richardson into coming back to the firm. A new partnership was formed known as Hodgetts, Richardson and Sons.'
However:
On Grace's guide entry for Benjamin Richardson it does not imply that at all. It just doesn't mention Jonathon Richardson after 1854
http://www.gracesguide.co.uk/Benjamin_RichardsonBenjamin Richardson
of Stourbridge, Worcestershire
1802 Born, ninth child of Joseph Richardson, a master furnace builder who had built the Wordsley Flint Glass House furnace in 1781.
Benjamin was to be the founder of one of the great English glass-manufacturing houses, instrumental in the introduction of modern glass-working methods to England. Richardson's Stourbridge factory was the first in the country to have a threading machine for making filigree glass and the first to make mass-produced pressed glass tumblers. The factory pioneered the use of pressing machines for decorating flint glass with relief ornaments. His firm also became one of the leaders in producing cameo glass for commercial sale.
Richardson is also remembered for his efforts to reduce the cost of manufacturing quality glassware, thus rendering it accessible to the general public.
Benjamin Richardson began at Thomas Hawkes where he learnt the trade eventually becoming manager.
1828 Benjamin Richardson was hired by the Wainwrights to re-open Wordsley Flint Glass Works which they had just purchased
1829 Richardson and Thomas Webb and his brother William Haden Richardson entered partnership as Webb and Richardson, taking over the Wordsley Glass Works.
1836 Webb left the partnership. The third Richardson brother, Jonathan, then joined the firm, which became known as W. H., B. and J. Richardson.
1854 He formed the partnership Hodgetts, Richardson and Pargeter with Jonathan Richardson, and their nephews Philip Pargeter and William James Hodgetts.
1871 Philip Pargeter left the partnership; Benjamin's son, Henry Gething Richardson, joined the partnership which then became Hodgetts, Richardson and Sons (1871-82)
1887 Benjamin Richardson died at the age of 85.
I suspect that since no one (who was writing about it) knew he had died, it has been 'assumed' that he was still in partnership with his brother Benjamin.