A mutiny or protest in which the 'mutineers' follow orders and regulations exactly; no more, no less. It may also include volunteering information only when asked, and interpreting orders as literally as possible ("you just said to turn on the machine, you didn't say anything about starting to work!").
This can be quite effective, since the primary value of a good worker is the ability to adapt to unforeseen conditions, and foresee and react to potential problems before they become serious. It also has the great advantage of not requiring the rebels to break any rules, ideally giving the current authority no reasonable grounds for complaint.
I haven't been able to find any information on the origin of the phrase, but everyone seems to agree that it has nautical origins, and it is particularly used in military settings (Navy and Marines).
A synonym for work to rule. See also, slow down strike.