Fec. and Ausf

[Warren O]

I read somewhere that Fec. means made by
what does Ausf mean? Is fec. the producer or the designer?
Examples are Fec Adolf Bock, Ausf Schwerin Berlin. You see the same with Otto Plazek and many others. Is Schwerin the producer or designer?
Warren

[Tom Yanacek]

I believe Fec. is from the Latin (fecit) which refers to the designer or artist of the piece. Ausfuhrung would indicate the manufacturer of the piece.