[silvr bull]

This problem arose several times before, but today was especially painful. LHO opened 1NT and RHO bid 2H, which was alerted as a transfer. But then LHO passed, and the defense was confused thinking declarer had Ss. When it became evident that declarer really had only two Ss and five Hs, I almost called the director, but I waited until the end of the hand. Looking at the hand later, there were no alerts and the opps did not claim to use transfers. The alert during play was a GIB thing that appeared to tell us what a robot would mean, but that was just false information for the system the human opps used. Is there any way to STOP the false GIB alerts when humans are playing?

[steve2005]

This can only happen in a 6-board tournament where everyone is supposed to playing GIB's card.

But sounds like opps were regular partners so they must have chosen as their CC one that self alerts like Gibs does, a SAYC card does this. As they are not playing transfersthey should not be using this cc and must make one of their one.

[barmar]

There are no GIB alerts in all-human tournaments. The only automatic alerts are if they're using a Full Disclosure convention card, and the whole point of this type of CC is that it displays explanations automatically.

If they're not actually playing the system that their CC claims, you should call the director.