Reference for Bava Batra 84:5

גופא אמר שמואל שותף כיורד ברשות דמי מאי קמ"ל שותפות אין לו חזקה לימא שותף אין לו חזקה

[To the question which is which,]<span class="x" onmousemove="('comment',' I.e., which kind of partner, according to Samuel, has hazakah and which has not. ');">⁹</span> some answer one way and some the other.<span class="x" onmousemove="('comment',' Some say that by taking possession of the whole field the partner acquires hazakah, because it is not usual for the other partner to allow this, and that by taking possession of one half, even the better half, he does not acquire hazakah, because one partner will often allow the other to do this several years running. Others say that by taking possession of the whole a partner does not acquire hazakah because it is the custom of joint owners that each should occupy the whole property several years running, but by taking possession of one particular half he does acquire hazakah because the presumption is that had the field not been divided he would not have confined himself to this particular half. ');">¹⁰</span>

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