It’s not a [i]Rosenthal[/i] mark but that of an (unidentified) decorator/studio which (re)decorated mainly [i]Hutschenreuther[/i] and [i]Heinrich[/i] items but also laid hands on a few [i]Tirschenreuth[/i] and other pieces.

The mark is a transfer application and covers the original mark which can often be made visible by holding a strong light source to the opposing side of the plate. Not that this changes anything in regard of desirability or “value”, it’s merely interesting side note.