(a) It is narrated from Abu Malik al-Ashja'i that he said: I said to my respected father: "Dear father, did you not pray behind the Messenger of Allah (peace and blessings be upon him), Abu Bakr and Umar (may Allah be pleased with them both)?" He said: "Certainly!" I said: "Did they recite the qunut in the Fajr prayer?" He said: "My son, that is an innovation."
(b) Tariq bin Ashyam al-Ashja'i did not retain the narration from those behind whom he prayed, so he considered it an innovation, whereas others besides him did retain this narration; therefore the ruling goes against him.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 3156