Reference for Bava Batra 251:9

ורב פפי משמיה דרבא אמר ויתר בכל הנכסים כולן קא סבר יש לו לבכור קודם חלוקה ומדאחיל בהא אחיל בכולהו

R. Assi said: If a firstborn son accepted a share [of a field]<span class="x" onmousemove="('comment',' Bequeathed by his father. ');">¹⁶</span> equal [to that of] any other [brother], he has renounced [the claims of his birthright]. What [is meant by] 'renounced'? — R. Papa said in the name of Raba: He renounced his claim upon that field only.<span class="x" onmousemove="('comment',' He may, however, still claim his rights in any of the other parts of the estate. ');">¹⁷</span>

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