I thought the thing was permanent. One thing though...They declare it to be effective... Has there ever been a market-wide halt since implementation? Did the breaker ever trigger? I remember it came close in Feb last year on the Dow, but not enough.
Talk of circuit breaker ALWAYS brings this to mind. This vid is only 3+ minutes and does not capture the final low or the retrace back. Circuit breakers of the day were not hit. AN AMAZING PIECE OF HISTORY.