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I'm not sure i get it right and i thoughts, in theory, it's not possible. But i stumbled with that transaction d5d27987d2a3dfc724e359870c6644b40e497bdc0589a033220fe15429d88599 and indeed, https://blockchain.info/tx/d5d27987d2a3dfc724e359870c6644b40e497bdc0589a033220fe15429d88599 two different blocks include that transaction.

Can someone explain me why and how does it happen?

Thank you

marked as duplicate by Nate Eldredge, Willtech, pebwindkraft, alcio, chytrik Mar 12 '18 at 6:35

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