Baba Batra 124 The disposition automatic revenue streams

A firstborn only receives a double portion from current holdings (mukhzak-מוּחְזָק) and not from any future assets (raooyi-רָאוּי). Daf TB Baba Batra 124 presents the disagreement between Rebbe (Rabbi Yehuda HaNasi) and the sages concerning the disposition of enhancements that come by itself. An example of this case would be rental property. The father owned property that he rented to others. These people paid rent on a regular basis. Since the rental money is an automatic revenue stream, is this account receivable considered current holdings and the firstborn receives a double portion or is it considered future assets?

Rebbe holds that the firstborn is entitled to his double portion because it is an automatic revenue stream; therefore, he considers it as a current holding. “And Rabbi Yehuda HaNasi says that the reason for his ruling that a firstborn receives a double portion of the enhancement is that the verse states: “A double portion” (Deuteronomy 21:17). It juxtaposes the portion of the firstborn to the portion of an ordinary son, in that just as the portion of an ordinary son is inherited even from property that did not reach the father’s possession before he died, so too, the portion of the firstborn is inherited even from property that did not reach the father’s possession before he died.” (Sefaria.org translation)

The sages liken the rental stream to a gift. “the reason for the ruling of the Rabbis that the firstborn does not receive a double portion of any enhancements that occur after the death of the father? The verse states: “Giving him a double portion” (Deuteronomy 21:17); by employing the term “giving” the Merciful One calls the double portion a gift. Just as a recipient of a gift does not acquire a gift unless it first reaches the possession of the one giving the gift, so too the firstborn does not acquire the portion of the firstborn unless it has reached the possession of the father before he died.” (Sefaria.org translation)

Even within the sage’s approach the sages, the amoraim of Babylonia and Eretz Yisrael disagree whether a firstborn would be entitled to a double portion if the estate has a loan document that includes an interest payment. The Babylonian amoraim consider the payment of the loan and the interest as account receivables; therefore, the firstborn would not be entitled to a double portion. The Eretz Yisrael amoraim hold that the loaned money is considered part of current holdings and the firstborn would be entitled to a double portion. However, any interest owed is considered future assets in the firstborn is not entitled to a double portion.