to verify whether or not goals have been scored. It states that "the use of GLT must be stipulated in the respective competition rules". The Laws themselves are not specific as to the nature of Goal Line technology systems, however other documentation from FIFA, which is cited by the Laws, goes into more detail. The FIFA Quality Programme for GLT Testing Manual precisely define the requirements of the systems. Four basic requirements of a system are stipulated: The system must address only the matter of whether a goal has been scored or not. The system must be accurate. The system must indicate the scoring of a goal immediately, confirming this within one second. The system must communicate its information solely to the match officials (via vibration and visual alert on the referee's watch) FIFA have a system whereby a particular technology provider needs to show effectiveness to successfully obtain a license for their technology, then an installation within a particular stadium must pass a "final installation test" before use, and before each game the referee must check that the system is functional. Current implementation Due to the expense of goal-line technology systems, the technology is only currently used at the very top levels of the game. In domestic competition, goal-line technology is only regularly used in a few major European leagues: Serie A, the Bundesliga, the Premier League, the EFL Championship, Ligue 1 and selected matches in the Eredivisie. The only major league without it is La Liga. , FIFA's website list 109 stadiums with licensed GLT installations, 106 of which use the Hawk-Eye system. The other three use GoalControl, which is the other licensed provider. History Pre-implementation history Prior to 2012, competitions were unable to implement technology as provision was not made for it in the Laws. The Laws of association football are controlled by the International Football Association Board (IFAB), a body on which FIFA holds 50% of the voting power, sufficient to veto any changes to the laws. Pre-2011 Compared to other sports, association football was late to allow technology to assist with in-game decisions. The matter was a subject of debate within the game for over a decade with the game's lawmakers resisting calls for its implementation. Throughout the 2000s various incidents incited discussion as to the potential for goal-line technology or a 'phantom goal' in the game. The lack of use of technology in association