Multiple ron

Multiple ron is a case where a player's discarded tile (or a tile added to a kan) has been claimed for a win by more than one player. Most often, this involves the situation of double ron. In rare cases, it can also involve triple ron. The exact handling of the situation depends on the rule variations in use.

Multiple Wins

One variation is to award a win to every player with a winning hand. In this instance, the losing player pays for each winning hand separately.

The exact handling of riichi bets and renchan is subject to further variation. Usually, the riichi bets are awarded to the leftmost player who won (that is, the player whose turn would come next). If the other winning player(s) had declared riichi, they may be allowed to reclaim them, or they may all go to the same player.

Under some rulesets, if oya is one of the multiple winners, this will always result in a renchan. Under others, the deal will rotate unless oya is the leftmost winner.

Atamahane

An alternate common variation, called atamahane (head bump) is to award a win only to the leftmost player (that is, the player whose turn would come next). All other wins are ignored.

Scoring treatment

Wins may be treated differently according to the rules in effect in a pro league, a jansou (or chain), a game server, or an organization.

Location Winners Riichi deposits Current riichi sticks Bonus counters Dealership
Head bump1 1 Priority2 Priority Priority Priority
Tenhou 2 Priority Priority Priority Dealer keeps
Janryuumon 3 Priority Priority Priority Priority
Marchao 3 Implied » Priority Priority Priority
ZOO 2 Implied » Implied » Priority ...
麻雀WELCOME (AKIBA店) 2 Implied » Priority Priority Priority
Pattern (Fuchuu) 2 Priority « Implied Priority ...
Japanese Wikipedia Varies Implied » Priority Varies Varies
EMA2016 3 Priority Winners reclaim, rest priority Both Dealer keeps

1. Please note that many organizations use head bump rules. These include...
2. "Priority" designates current player priority (from discarder: Right > Across > Left), and not game seating priority as used to split ties on Tenhou (starting: East > South > West > North).

Chombo

If a player declares a false win at the same time as another player declares a real one, the chombo penalty is usually nullified. Some rulesets may, however, retain the full penalty, or provide that a lesser penalty be paid.

Sanchahou

The final variation, applicable only in the case of triple ron, is called sanchahou. If this rule is being used, a triple ron results in an abortive draw and the hand is replayed. The player who was called off of escapes having to pay for three hands.

Under an uncommon rule variation, if a double ron occurs, the final player must reveal their hand to prove that they could not have legally called ron (including due to furiten). If they could have, then the hand is still an abortive draw. This rule is to prevent a player from choosing not to call ron after hearing that two other players have done so.