Disallow A’s protest. When A reached the zone, the rights and obligations in rule 18.2(a), Giving Mark-Room, depend on whether the boats are “overlapped” at that time. The definition Clear Astern and Clear Ahead; Overlap states: “One boat is clear astern of another when her hull and equipment in normal position are behind a line abeam from the aftermost point of the other boat’s hull and equipment in normal position. The other boat is clear ahead. They overlap when neither is clear astern. However, they also overlap when a boat between them overlaps both.”

Because C was overlapped with B, and B was overlapped with A when A reached the zone, by definition, C was “overlapped” with A. Therefore, A was required to give both B and C mark-room under rule 18.2(a)(1), which she did.