Reference for Shabbat 9:4

ודילמא הנחה הוא דלא בעינן הא עקירה בעינן והנחה נמי דילמא דפשיט כנפיה וקיבלה דאיכא נמי הנחה

For it was taught: Others say: If he stands still in his place and catches it, he [the thrower] is liable; if he moves from his place and catches it, he [the thrower] is exempt.<span class="x" onmousemove="('comment',' If A throws an article in the street to B, and B catches it while standing in his place, A is liable, because he is regarded as having both removed and deposited it. But if B moves away and catches it, A did not effect its deposit, since it does not lie where it would have done on account of his throw. ');">⁴</span>

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