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Hi. The short answer is 'No' - maker not known.
There will be two articles in the PCA Bulletin 2016 (one by me, one by Paul Dunlop) concerning a couple of factories that probably made these doorknobs and a whole range of high quality paperweights (millefiori patterns, colour grounds, sodden snows etc) that have been wrongly attributed over the years, often to Clichy. The doorknobs have been called all kinds of things : Dorflinger, Saint-Louis, Clichy, St Mande...but these attributions are almost certainly wrong. There is always some doubt because canes can move around between factories, but Paul thinks an unknown French factory, whereas I think they may be from an unknown Belgian factory (I am sure some of the paperweights are Belgian). I think they are closely linked to the 'starfish cane' paperweights, about which I have written a couple of articles. Whoever made them, they are quite nice pieces, and always similar in style. If you search Google images for millefiori doorknob you will find some more examples.
I have attached an image of a couple I used to own.
Alan