Showing One Card (after everyone has folded)

[jeffnc]

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At a home game, I raised some girl off of her AQ on a Qxx board, and I showed my Q. Her boyfriend reached over and flipped my 2nd card from the muck, claiming the "show one show all" rule.

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He's a complete idiot.

There are 3 rules.
1) "Show one show all" - "one" and "all" refer to people, not your cards. If any player at the table has seen any of your cards, you have to show them to every other player.

2) "Show both cards to win" - at showdown, if you are making a claim at the pot, you have to show both your cards. You cannot just show one card (for example, if there are 3 aces on the board, and you have the other ace in your hand for the nuts, you cannot just show 1 ace to take the pot. You have to show both cards. Even if the board has the nuts and you are splitting the pot.

3) "Show both cards if you show one" - if you show one card voluntarily to an opponent, you have to show both of them.

Rules 1) and 2) are pretty much universal and strictly enforced everywhere. Rule 3) is only in place at some places, not all.