Any property that is acquired by the Karta while the joint family exists is simply presumed to be joint family property if ancestral income is utilised in any part of the purchase.
The burden of proof in such cases lies with the Karta to clearly demonstrate the exact portion funded through personal funds and earnings. In case of absence of clear documentation or other forms of satisfactory evidence, subject to the satisfaction of the court, the property is fully considered joint family property.
In specific cases where funds from ancestral and personal sources are ‘intermingled’, courts do not encourage separating them unless clear records exist. This approach ensures that disputes are not entertained on vague personal claims.
Judgements have put the responsibility of proving self-acquisition on the claimant. This means that if you are a Karta and you claim self-acquisition, you must back it up with solid evidence.