Is reading the Qur’an in one house by ten people, on one night, and without charge considered an innovation (bid‘ah)?

Gathering to recite the Qur’an is among the best deeds, whether in the mosque or at home, though the mosque is superior. The legitimate manner of recitation is for one person to recite and another to continue, while the rest listen and correct errors; this is called "Idarah" recitation. As for reciting in a single voice, there is a detailed explanation mentioned in a previous fatwa (definition). If their recitation is free from innovations (bid'ah) and reprehensible acts (munkarat), they will be rewarded. And if they complete the entire Qur’an in one night with proper recitation, that is a good thing.