Neil Parmentier and Sieg Brunnenkant

Neil Parmentier and Sieg Brunnenkant were the key figures behind the Mercator 30 (also known as the Offshore 30 Mercator), a 30-foot masthead sloop coastal cruiser built in fiberglass in Kent, Washington, USA, from 1968 to 1981 (38 hulls total).
Neil Parmentier was the original designer and molder: He personally molded the early hulls and sold them as bare hulls for owner completion. He is credited as the primary naval architect for the boat's lines and initial development.
Sieg Brunnenkant collaborated with Parmentier around 1970 to refine the design: They redesigned the hull, created molds for a new deck and coachroof (resulting in the Mark II version with a fiberglass rounded house vs. earlier squared wooden one), and founded Mercator Industries together. In 1973, Parmentier sold his interest to Brunnenkant, who continued building the boats until 1981.

This partnership produced a sturdy, moderate-displacement fin-keel sloop (with skeg rudder) known for solid hand-laid fiberglass construction and practical cruising features. The boat's evolution from bare hulls to the completed Mark II reflects their joint work on improving deck/house design and production efficiency.