user37605: Let's asume I make a transaction with no fee and doesn't get confirmed after a while (let's say 10 days).
Could it be confirmed after that if for some reason some miner keeps a copy? I don't ask if is likely to happen but if it is posible.

user85: Absolutely. There are cases of transactions remaining unconfirmed for several days and then getting confirmed.
If the transaction was ever broadcast and is still valid, it can be included in a block by any miner who wishes to include it.

37605: <p>Let's asume I make a transaction with no fee and doesn't get confirmed after a while (let's say 10 days).</p>

<p>Could it be confirmed after that if for some reason some miner keeps a copy? I don't ask if is likely to happen but if it is posible.</p>
 85: <p>Absolutely. There are cases of transactions remaining unconfirmed for several days and then getting confirmed.</p>

<p>If the transaction was ever broadcast and is still valid, it can be included in a block by any miner who wishes to include it.</p>
