The Gemara relates: There was a certain document that had the signatures of two individuals on it. One of the signatory witnesses died, and when the court sought to ratify the document, which requires either that the witnesses personally attest to the validity of their signatures or that two other witnesses attest to the validity of the signatures, the brother of the witness who remained alive and one other individual came to testify with regard to the signature of the other, deceased, witness, while the living witness attested to his own signature.

Ravina thought to say that this case is the same as the halakha in the mishna, which states that if testimony was given by three brothers, each of whom testify about one year, and another, unrelated individual joined with each of the brothers as the second witness, these are considered to be three distinct testimonies. Similarly, in this case, one brother attests to his own signature, while the other brother attests to the signature of the deceased witness.

Rav Ashi said to him: Are these cases comparable? There, the property less one-quarter, i.e., three-quarters of the property in question, is not removed from the possession of the prior owner based upon the mouth, i.e., the testimony, of brothers. Each brother provides only half of the testimony for each year about which he testifies. Here, the property less one-quarter is removed from the possession of the debtor detailed in the document based upon the mouth of brothers. One brother attests to his own signature, which constitutes half of the testimony, while the other signature is authenticated by the testimony of the other brother and another individual. It follows that three-quarters of the testimony is given by brothers, and it is therefore invalid.

MISHNA: These are uses of property that have the means to establish the presumption of ownership, and these are uses of property that do not have the means to establish the presumption of ownership: If one would stand an animal in a courtyard; or if one would place an oven, a millstone, or a stove there; or if one raises chickens in a courtyard, or places his fertilizer in a courtyard, these actions are not sufficient to establish the presumption of ownership. But if one constructed a partition ten handbreadths high to contain his animal, and similarly if he constructed a partition for his oven, and similarly if he constructed a partition for his stove, and similarly if he constructed a partition for his millstone; or if one brought chickens into the house, or if he fashioned a place in the ground for his fertilizer that is three handbreadths deep or three handbreadths high, these actions are sufficient to establish the presumption of ownership.

GEMARA: The Gemara asks: What is different in the first clause, where having an animal stand in a courtyard is insufficient to establish the presumption of ownership, and what is different in the latter clause, where constructing a partition is sufficient to establish the presumption of ownership?

Ulla says: With regard to any act which, if one were to perform it on ownerless property such as the property of a convert who dies without heirs he would acquire that property, that same act is sufficient for him to acquire the property of another if he performed it over the course of three years, provided it is accompanied by the claim that the property had been purchased. Conversely, any act that if one were to perform it on the property of a convert who died without heirs he would not acquire that property, that same act is sufficient for him to acquire the property of another. Taking possession of ownerless property requires an act to be done with regard to the property itself, such as constructing a partition, but merely having an animal stand there is not sufficient. Therefore, it does not establish the presumption of ownership.

Rav Sheshet objects to this explanation: And is this an established principle? But there is plowing, which, if performed on the property of a convert who died without heirs one acquires it, but if performed on the property of another one does not acquire it. And additionally, there is consumption of produce for the duration of three years, which, if performed on the property of another one acquires it by establishing the presumption of ownership, but if performed on the property of a convert who died without heirs one does not acquire it. These cases contradict Ulla’s claim that the modes of acquisition are analogous.

Rather, Rav Naḥman said that Rabba bar Avuh said: