The founder of the world's first Fair Trade-certified shrimp producer has resigned -- as has much of the company's staff -- over a disagreement with some of the group's shareholders.

Sergio Castro, founder and CEO of California-based Del Pacifico Seafoods, told IntraFish on Wednesday that he and the entire US team and the majority of the Mexico team have left the company, including procurement, processing, sales and marketing staff.

Mexico-based investment company GCI is a major shareholder in the company.