These cases are very common in various Courts of India. I can understand your concern in this regard. My team has dealt with various cases of such nature.
Hon'ble Supreme Court in the case of D.S. Lakshmaiah and Another Vs. L. Balasubramanyam (2003) held that the legal principle is that there is no presumption of a property being joint family property only on account of existence of a joint Hindu family. The one who asserts has to prove that the property is a joint family property. If, however, the person so asserting proves that there was nucleus with which the joint family property could be acquired, there would be presumption of the property being joint and the onus would shift on the person who claims it to be self-acquired property to prove that he purchased the property with his own funds and not out of joint family nucleus that was available.
In Sher Singh Vs. Gamdoor Singh (1997), the Hon’ble Supreme Court said that once existence of a joint family is not in dispute, necessarily the property held by family assumed the character of a coparcenary property and every member of family would be entitled, by birth, to a share in coparcenary property, unless any one of the coparcener pleads, by separate pleadings and proves, that some of the properties or all the properties are his self-acquired properties and cannot be blended in coparcenary property. Merely because the family is joint, there is no presumption of joint property. A Hindu, even if he be joint may possess separate property. Such property belongs exclusively to him. Neither member of the coparcenary, nor his male issue, acquires any interest in it by birth. On his death (intestate), it passes by succession to his heirs and not by survivorship to the surviving coparcener. The existence of joint family does not raise presumption that it owns properties jointly. But once joint family nucleus is either proved or admitted so as to draw inference that such property could have been acquired out of joint family funds, the burden shifts to the party alleging self acquisition, to establish affirmatively, that such property was acquired without aid of joint family. Initial burden always lies upon the party asserting that any item of property is joint family property.
In another case of Rukhmabai Vs. Lala Laxminarayan (1960) Hon’ble Supreme Court held that there is a presumption in Hindu Law that a family is joint. There can be a division in status among the members of a joint Hindu family by refinement of shares which is technically called "division in status", or an actual division among them by allotment of specific property to each one of them which is described as "division by metes and bounds". A member need. not receive any share in the joint estate but may renounce his interest therein, his renunciation merely extinguishes his interest in the estate but does not affect the status of the remaining members vis- a-vis the family property, A division in status can be effected by an unambiguous declaration to become divided from the others and that intention can be expressed by any process. Though prima facie a document clearly expressing the intention to divide brings about a division in status, it is open to a party to prove that the said document was a sham or a nominal one not intended to be acted upon but was conceived and executed for an ulterior purpose. But there is no presumption that any property, whether movable or immovable, held by a member of, a joint Hindu family, is joint family property. The burden lies upon the person who asserts that a particular property is joint family property to establish that fact. But if he proves that there was sufficient joint family nucleus from and out of which the said property could have been acquired, the burden shifts to the member of the family setting up the claim that it is his personal property.
Therefore, in case your father’s brother and his sons are able to prove that it was joint family property and it was purchased out of family money, then the you and your father have to prove that property was purchased out of independent income. Detailed discussion is required with complete documents of the case which other side has initiated.
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