Below is an interesting email from Miles Stair...
The Valor 525 was made in England and distributed throughout the Commonwealth and is a direct Perfection clone. The Moonlighter heater from Toyotomi of Japan was a miniaturized Perfection with distinct improvements - a 1.9 gallon tank so it would not run out of fuel overnight, an igniter, wide base for stability, etc.
The reason there were so many clones is that the 1913 Perfection patent was for their flame spreader. As the first thimble-style flame spreader was the Henkle patent of Jan. 15, 1884 and many other patents for flame spreader designs were made and in use for 28 years before the Perfection patent.
The Perfection wick of 2 1/2" diameter was in fact a store lamp wick in a carrier. Rochester originated that wick for their 1884 store lamp - I have one! B&H, Cleveland, Parker and Miller all made heaters using the store lamp wick from the late 1880's on, all established long before the Perfection heater was introduced.
As a result, Perfection could not "defend" their patent, did not even try, so anyone who wanted to clone their heater could do so.