There is a difference of opinion in regards to this query:
1. Ayatullah Khoie and few other scholars : The present version of the Qur'an is the same which used to be at the time of prophet.
2. Other scholars: The Qur'an was compiled after the demise of the holy prophet (pbuh). Imam Ali (as) and other companions such as Zayd b Thabit and others played a vital role in compilation of Qur'an.
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