At the very least, you move *out* of the left lane to permit faster traffic to pass. Here's a Florida statute that applies:
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Title XXIII
MOTOR VEHICLES Chapter 316
STATE UNIFORM TRAFFIC CONTROL
316.083 Overtaking and passing a vehicle.--The following rules shall govern the overtaking and passing of vehicles proceeding in the same direction, subject to those limitations, exceptions, and special rules hereinafter stated:
(1) The driver of a vehicle overtaking another vehicle proceeding in the same direction shall pass to the left thereof at a safe distance and shall not again drive to the right side of the roadway until safely clear of the overtaken vehicle.
(2) Except when overtaking and passing on the right is permitted, the driver of an overtaken vehicle shall give way to the right in favor of the overtaking vehicle, on audible signal or upon the visible blinking of the headlamps of the overtaking vehicle if such overtaking is being attempted at nighttime, and shall not increase the speed of his or her vehicle until completely passed by the overtaking vehicle.
(3) A violation of this section is a noncriminal traffic infraction, punishable as a moving violation as provided in chapter 318.
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Note that the law says nothing like "except when the overtaken vehicle is traveling at the posted speed limit".
If you're overtaken by another vehicle, you move out of the way. Perhaps the hope is by passing a new (redundant) law, just the media attention will cause an improvement in driving habits. IOW, this is cheaper than tasking the police with *enforcing* the existing law.
That statute is referring to passing on single-lane roads. It is wholly inapplicable to the discussions on this thread.