Is it obligatory for the congregant to recite Al-Fatiha after the Imam has recited it in the loud prayer, and what is the ruling on reciting it with him, and should he complete it if the Imam bows while he has only recited a quarter of it, and is its recitation obligatory if he is reciting the opening supplication?

The preponderant view is that Al-Fatihah is one of the pillars of prayer, and the prayer is not valid without it, whether for the Imam, the congregant, or the individual. It is permissible for the congregant to recite it along with the Imam's recitation. It is preferable for the congregant to recite it after the Imam has finished it, if the Imam pauses, to enable the congregant to recite it. It is sunnah for the Imam to pause after Al-Fatihah. If the congregant recites Al-Fatihah with the Imam and finishes it before him, he should not say 'Ameen' until the Imam says 'Ameen'. The correct view is that he says 'Ameen' for his own recitation, and then says 'Ameen' again with the Imam's 'Ameen'. If we say that the congregant recites in a loud prayer, it is disliked for him to raise his voice in a way that disturbs his neighbor; rather, he should recite quietly, audible only to himself.

If the Imam precedes the congregant in part of Al-Fatihah, and the Imam bows before the congregant completes it, then the congregant bows with the Imam, and the rest of Al-Fatihah is dropped for him. This is the madhhab according to the Shafi'is.

If the Imam precedes the congregant in the opening supplication (Du'a al-Istiftah), so the Imam is reciting Al-Fatihah while the congregant is reciting Du'a al-Istiftah, then the congregant should not recite Du'a al-Istiftah in this case. Rather, he should hasten to recite Al-Fatihah, unless he is confident that he can recite the Ta'awwudh (seeking refuge), Du'a al-Istiftah, and then Al-Fatihah before the Imam bows. In that case, it is recommended for him to recite the Ta'awwudh and Du'a al-Istiftah. If the Imam bows before the congregant completes Al-Fatihah, then the congregant bows and the rest of Al-Fatihah is dropped for him. If the congregant has recited some of the Ta'awwudh and Du'a al-Istiftah, he must recite from Al-Fatihah an amount equal to what he recited from the Ta'awwudh and Du'a al-Istiftah.