Bidding box

Their usage eventually spread in Europe, United States and around the world, and today they present a virtually indispensable piece of equipment even for home-played games.

On the backside of each bidding card are written up all possible results of the corresponding contract: if made exactly or with extra tricks; if doubled or redoubled; both non-vulnerable and vulnerable.

The latter has the advantage that it does not occupy space on the table, but it can hamper the players' passage to and from their seats, so it gets damaged more easily.

In some tournaments an L-shaped metal bracket is slid under the tabletop corners, leaving its other end standing up.

In addition, oral bidding causes noise in tournament halls, and auctions can be easily overheard at the other tables.

Bidding boxes were invented in 1962 in Sweden by Gösta Nordenson[1] and first used at a World Bridge Championships game in Stockholm in 1970.

The additional (non-call) cards are used as follows: The exact regulations for the use of bidding boxes vary according to the sponsoring authority.

In tournaments sanctioned by the ACBL, for example:[8] Use of bidding boxes greatly improves the game for people with hearing impairment.

[9] Conversely, players with certain physical impairments (blindness, arthritis) may be unable to use bidding boxes and are exempted from their use.

That makes it somewhat difficult for left-handed people, who naturally bid with their left hand: they would normally hold the box at the left side of the table, and the card symbols on standard boxes turn upside down unless rotated in an awkward manner.