The rule of Kuikae, sometimes used in Japanese Mah Jong, forbids a player to break an existing set and immediately discard a tile which would form a Chow or Pung with the two tiles he just melded as a part of the set he completed after claiming another player's discard (i.e., a tile identical with the claimed tile or a tile 3 numbers different from the claimed tile which can form a sequence with the two tiles just melded).
E.g., if a player has Bamboo 1-2-3 in hand and he claims Bamboo 4 from another player, he is not allowed to immediately discard Bamboo 1 (nor Bamboo 4). Or if a player has a Pung of Dot 3 in the hand and he claims Dot 3 from another player and composes a melded Pung, he is not allowed to immediately discard the fourth Dot 3.
Note: Should the player get in a situation where he is about to break an existing set and cannot make any discards because of the rule of Kuikae, his claim is canceled and appropriate penalty for faulty claim is applied. It is recommended that the rule is not used with modern pattern-based rules, where players are encouraged to improve their hands and where discards prohibited by the rule of Kuikae might be quite reasonable.
Related topics:
Claiming rules – Chows
Claiming rules – Pair
Claiming rules – Over-claiming
Claiming rules – Sacred Discard
Claiming rules – Missed Discard
Claiming rules – Competitive claims for going out