Steinberg & Einwaldt / W. Einwaldt (Inhaber H. Einwaldt)
Spandauerstraße, Heiligegeiststraße 49, Neue Promenadestraße 6, Rosenthalerstraße 40, Alte Schönhauserstraße 29, Berlin, Prussia (now the Federal City State of Berlin).
Glas- und Porzellanhandlung / Glass and Porcelain Wholesaler
Supposedly founded in 1845, but first listed as Steinberg & Einwaldt in 1847 at Spandauerstraße 59. In 1849 W. Einwaldt was trading by himself at the same address.
The company was trading until 1942.
Purchased stein bodies from: Villeroy & Boch - Mettlach.
Reference: Berliner Adressbücher Berlin Postcodes
Ink stamp on Villeroy & Boch - Mettlach #1431. "Actien-Brauerei. Friedrichshain". 
Villeroy & Boch - Mettlach #1431. "Actien-Brauerei. Friedrichshain". 
Decorator's / Vendor's rubber stamp on a Villeroy & Boch - Mettlach #1526, dated 1907. 