General average losses require what from the parties involved?

The correct answer highlights the principle of shared proportional losses among owners in the context of general average losses. General average is a maritime law concept that applies when there is a loss or damage incurred during a voyage, necessitating that all parties involved in the shipping venture contribute proportionally to recover losses.

When a vessel encounters a situation—such as having to jettison cargo to save the ship and crew—the losses are not borne solely by the owner of the lost cargo but are distributed among all parties based on the value of their remaining cargo. This equitable sharing ensures fairness and encourages cooperation among owners during challenging circumstances.

This principle is crucial in maintaining the integrity of commercial shipping and encourages proactive measures to address potential risks. Each owner thus assumes a portion of the loss relative to their stake in the voyage, which aligns with the overall concept of mutual interest in a maritime operation.