Reference for Chullin 271:65

מתני'

And should you say that this is indeed so,<span class="x" onmousemove="('comment',' That fleece which had grown on sheep while in the possession of a gentile, although now in the possession of an Israelite, is exempt from the first of the fleece.');">⁴⁶</span> but we have learnt: IF A MAN BOUGHT THE FLEECES OF A FLOCK BELONGING TO A GENTILE HE IS EXEMPT FROM THE LAW OF THE FIRST OF THE FLEECE, so it follows that if he bought the flock [with its fleece] which was ready for shearing he would be liable!<span class="x" onmousemove="('comment',' Although the wool grew upon the sheep whilst they were in the possession of the gentile.');">⁴⁷</span> - Our Mishnah

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