It may well be that claret would be more of a problem on white linen table cloths, rather than the table - or perhaps even the butler's gloves.
The image in The National Archives at Kew, for Rd. 282496 dated 20th May 1874, is described as a design for 'The drip cup claret Jug', and does match the three examples shown here - and a record of the Rd. No. can be seen in Thompson, for example, as Parcel 10.
None of the examples shown here includes a stopper that matches the drawing from 1874 - it seems there should be a small nipple like protrusion on the very top of what I assume was originally a hollow ball stopper - difficult to tell from drawings, but probably hollow.
The original drawing includes the names of...........Percival Jones, China & Glass Merchants, 15 Westmorland Street, Dublin..............and Philip Pargeter, Glass Manufacturer of Stourbridge.......................for some reason both names and addresses have pencil crosses through them.
I've had a look but can't see this design in Andy McConnell's book under the heading of Claret Jugs. The original Registration details include both names, and although it may well be that this was a Pargeter & Jones design, the records don't specifically say this.
I notice that Mark West states that this jug is from the 'Red House Glass Works', which seems to fit in with the the fact that Philip Pargeter departed from the company of Hodgetts, Richardson & Pargeter at the Wordsley Glass Works around 1869, to run the Red House cone which he started some time in 1871, presumably with someone called Mr. Jones.
If it's true that there aren't any examples which include a lozenge, then someone somewhere has done their homework in locating the design from the Kew records - so well done someone.
Hope this is of interest.