>"B. m. gen.
>frå garden eller staden der ein er: koma frá konungs,
>frå kongen; sjeldnare i tyding A 7: þetta var flutt
>frá hans (fortalt om han)." (Heggstad et al. pagina
>123)
Yes. This is a usage similar to that of English:
They are at Hawk's.
Þeir eru at Hauks.
Where "Hawk's" stands for "Hawk's place".
Similarily:
Þeir koma frá konungs. = They're coming from the king's [place].