More info, this time from:
http://www.mbsi.org/journal/MBSI-1977-23-3/MBSI-1977-23-3-37.pdf “The first reference to the firm Berens Blumberg & Co. in the directories appeared in 1829 when it was listed at A O B Berens & Co., Importeres of French fancy articles etc., 21 St. Paul’s Churchyard. In 1830 L. Blumberg had joined Berens and the address was 20 St. Paul’s Churchyard. From 1833 a Paris address was also given: this was 8 Rue de Vielles Audriettes until 1837, and from 1868 was 60 Rue de Bondy.
In 1861, the firm was listed as Blumberg & Co. (late Berens, Blumberg & Co.), importers of and dealers in French, German and British fancy goods, stationery, cabinet work, perfumery, jewellery, musical boxes, watches, clocks, china, glass, etc., 55 Cannon St. West, and 64 Rue de Bondy. Blumberg & Co. was listed at various addresses in the City of London UNTIL 1886, AFTER WHICH IT DISAPPEARED FROM THE DIRECTORIES” [my capitals for emphasis].
It would appear then that RD 44546 of 1886 was registered right at the end of Blumberg & Co.'s commercial life.
Fred.