On a downwind leg, Yellow is sailing in an attempt to pass astern of Blue. Blue rapidly luffs, and tacks to leeward of Yellow. At all times Yellow is turning to keep clear.

There is a protest? What rules if any have been broken?

 

 

screen-shot-2016-10-28-at-11-57-23

Check the Rules Explanations section at the bottom left of the home page.