In Shia Muslim marriage, how many witnesses are compulsorily required?

Witnesses are not an essential validity requirement for a Shia marriage; therefore no witness is compulsorily required in the personal-law sense asked here. Faheem Ahmed expressly distinguishes this from the Sunni witness rule. Proof of a disputed marriage, registration formalities and the separate witness requirements for certain divorce forms are different questions.

Current law: For people governed by Uttarakhand Code, sections 4–6 provide uniform marriage conditions, permitted ceremonies and registration. That does not justify importing a Sunni ceremony-witness rule into the historical Shia question; current statutory formalities and scope must be checked separately.