Many thanks to Pete for his detailed research. I have a Lyon & Lyon shotgun that readers may be interested in. It is a 20 gauge sidelock ejector with nitro steel barrels likely made in the late 1890's or early 1900's. The rib is engraved in bold gold lettering "LYON & LYON. LONDON & CAlCUTTA. (J. LYON. LATE WITH JAS PURDEY & SONS LONDON.)" Each lock is engraved in gold "LYON & LYON".There is no indication who made the gun but the underside of the forend iron is marked Patent 556 which might a lead.
If you can date the gun to within 2-3 years, I may be able to help. I have all 7 volumes of the British Small Arms patents. Unfortunately, they are not easy to referrence without a year.
I was able to pull this, not much help.
A.J. Lyon 128,824
J Lyon '13.22,939
L.I. Lyon '68.2,096
Lyon & Lyon 279,371
A.J. Lyons '06.12,474
Pete
