Slam-seeking conventions Slam-seeking conventions Slam-seeking conventions are codified artificial bids used in the card game contract bridge. Bidding and making a small slam (12 tricks) or grand slam (13 tricks) yields high bonuses ranging from 500 to 1500 points. However, the risk is also high as failure to fulfill the slam contract also means failure to score the bonus points for a game (300-500). Conventions have been devised to maximise the opportunity for success whilst minimising the risk of failure. Contract bridge bidding systems are mainly "natural" (most bids have an obvious meaning) or "artificial" (many bids have a meaning unrelated to
Bidding box in 1962 in Sweden by Gösta Nordenson and first used at a World Bridge Championships game in Stockholm in 1970. Eric Jannersten, a Swedish social bridge player and founder of the largest European bridge equipment manufacturer, Jannersten Förlag AB bought the patent in 1970 being attributed by some as the inventor. However, the patent is disputed by the Swedish Bridge Federation. They quickly became popular in Europe, and after some resistance were accepted in American bridge clubs. , they are practically an indispensable part of the game, and even many rubber bridge players use them at home. Use of bidding