The Mercantile Guilds and Dynasties within Rebma operate outside much of the socially accepted Rebman norms. Due to the nature of trade, the oppressions that face men in most strata of Rebman society are significantly reduced within the guilds. Members of the Noble Houses who hold interests in trade must deal with the Trade Council & Guilds, and as such, are expected to respect the way the mercantile structures work.
As with much of Rebma, families who have controlling interests in trade practice female inheritance. Unlike the rest of Rebma, men do hold positions of power within trade dynasties, and can be considered equals to many of their female counterparts. And as Cyfrif (Matriarchs) frequently nominate their heirs (a practice thought to have come from their contact with trading houses of Amber, and House Chantris), it is possible that a female successor could come from a male line. Outside of the trade dynasties, there are many smaller merchant families who seek to foster their children to members of the major houses as best they can. It is not always blood which defines an heir. A much valued foster child will be just as likely to inherit within a trade dynasty as those of the blood.
Naming conventions within Trade Dynasties also follow matronymic nomenclature, and additionally include dynastic allegiance. For example, Florrynce daughter of Gherys is a blood member of the Teisen trade dynasty. She would be recognised as Florrynce Teiseneva rch Gherys, her brother, Gheirent Teisenych rch Gherys.
Those children fostered in to the trade dynasties add dynastic allegiance to the end of their names, e.g. Neris rch Brydda y Teisen. Foster children who become Cyfrif of a Trade Dynasty by inheritance drop their mothers name altogether, e.g. Neris rch Brydda y Teisen would become Neris y Teisen, and her natural children would be of the blood and follow standard naming conventions, regardless of her origins.
The biological families of foster children benefit greatly from their associations, as it puts them in better positions to conduct trade under the umbrella of a dynastic name.
There are four major Trade Dynasties in Rebma. Mostyn, Treharris, Gedrych, and Teisen. These dynasties can trace their roots in trade back to the Industrial Renaissance.