Yes, and this represents one of the most fundamental and frequently successful grounds for challenging a Will in Mumbai, since proper attestation by witnesses is not merely a formality but an absolute mandatory requirement under Indian succession law, without which a Will simply cannot be considered validly executed. Under Section 63 of the Indian Succession Act, 1925, every Will must be attested by at least two or more witnesses, each of whom must have seen the testator sign or affix their mark to the Will, or have seen some other person sign the Will in the testator's presence and by their direction, and each witness must sign the Will in the presence of the testator, though the witnesses need not necessarily be present at the same time as each other.

Where a Will lacks proper witness signatures altogether, or where the attestation is defective in some material way — such as witnesses who didn't actually observe the testator's signing, witnesses who signed at a different time or without the testator's presence, or a document with only one witness rather than the mandatory minimum of two — this constitutes a fundamental defect that renders the Will invalid and unenforceable, regardless of how clearly it might otherwise express the testator's genuine wishes. Courts apply this requirement strictly, since the witness requirement serves the crucial purpose of providing independent verification that the testator genuinely executed the document with full understanding and voluntary consent.

To successfully challenge a Will on grounds of improper attestation, the challenging party typically needs to examine the document itself for the presence and apparent validity of witness signatures, and where witnesses are named but their actual presence and observation during execution is disputed, the challenge often requires examining the witnesses themselves, or in their absence, other evidence establishing whether proper attestation genuinely occurred at the time of signing. Where a purported witness later testifies they didn't actually witness the testator signing, or that they signed the document at a completely different time without the testator being present, this directly undermines the Will's validity under the strict requirements of Section 63.

Where the Will's propounder — typically the executor or a beneficiary seeking to establish the Will's validity — cannot produce credible evidence of proper attestation, whether through the surviving witnesses' testimony or other compelling circumstantial evidence, courts generally will not admit the Will to probate, since the burden of proving due execution, including proper attestation, rests squarely on whoever seeks to establish the Will's validity, not on the challenger to disprove it.

Given how attestation defects provide such a fundamental and often clear-cut ground for challenging a Will's validity, careful examination of the document's execution circumstances is essential both for those seeking to challenge a Will and executors seeking to defend one. Our legal experts at Aapka Legal Advice examine Will attestation carefully to assess challenge or defence strategies in Mumbai succession disputes. The Top Property Lawyers in Mumbai team has successfully challenged and defended Wills on attestation grounds before Mumbai's civil courts, supported by a panel of retired judges experienced in testamentary matters and criminal lawyers where forgery of witness signatures is suspected. If you're examining a Mumbai Will's validity, carefully reviewing whether proper attestation under Section 63 of the Succession Act genuinely occurred is often the most direct path to assessing a potential challenge.