It was narrated from Abu Malik Al-Ashja'i that his father said:

"I prayed behind the Messenger of Allah ﷺ and he did not say the Qunut, and I prayed behind Abu Bakr and he did not say the Qunut, and I prayed behind Umar and he did not say the Qunut, and I prayed behind Uthman and he did not say the Qunut, and I prayed behind Ali and he did not say the Qunut." Then he said: "O my son, this is an innovation."

أَخْبَرَنَا قُتَيْبَةُ، عَنْ خَلَفٍ، - وَهُوَ ابْنُ خَلِيفَةَ - عَنْ أَبِي مَالِكٍ الأَشْجَعِيِّ، عَنْ أَبِيهِ، قَالَ صَلَّيْتُ خَلْفَ رَسُولِ اللَّهِ ﷺ فَلَمْ يَقْنُتْ وَصَلَّيْتُ خَلْفَ أَبِي بَكْرٍ فَلَمْ يَقْنُتْ وَصَلَّيْتُ خَلْفَ عُمَرَ فَلَمْ يَقْنُتْ وَصَلَّيْتُ خَلْفَ عُثْمَانَ فَلَمْ يَقْنُتْ وَصَلَّيْتُ خَلْفَ عَلِيٍّ فَلَمْ يَقْنُتْ ثُمَّ قَالَ يَا بُنَىَّ إِنَّهَا بِدْعَةٌ .