Click here to view as a PDF or print.

Rev 9/14/13

1.  Suction is approved as a defense on the GCC for overcalls of conventional calls such as a strong 1♣ or 2♣ opening bid.

2.  Suction is not approved as a defense on the GCC for direct seat overcalls of natural notrump opening bids or natural notrump overcalls. Since the word “direct” is used in the definition the implication is that it may be used in balancing seat. 


a) Conventional calls (except see #10 RESPONSES and REBIDS above and #7 under DISALLOWED below),

b) Natural notrump opening bids and notrump overcalls, except that direct calls, other than double and 2must have at least one known suit.

c) Opening bids of two clubs or higher

3.  A district has the right to include Mid-Chart Conventions at a Sectional or a Regional (see number 4 below), but they may not dictate to clubs the inclusion or exclusion of any convention. The district should note the underlined part below:

This chart (the Mid-Chart Conventions) applies to:

1. All NABC+ events with no upper masterpoint restrictions played at an NABC.

2. All unrestricted Flight A regional rated events at an NABC.

3. Any bracket of a bracketed KO at an NABC which contains no team with an average masterpoint holding of fewer than 1500 points.

4. Provided it has been included in tournament advertising, this chart (or any part) may apply to any sectional or regional rated event or tournament at the sponsor’s option. The requirement for advertising does not extend to use in Flt. A or KO brackets which contain no team with an average masterpoint holding of fewer than 1500.” 

5.  Clubs are their own regulating authority (whether it be a board or manager/owner) when it comes to conventions allowed or disallowed in games.  From the ACBL handbook: 


Club managers may regulate conventions in games conducted at their clubs. A complete list of conventions that may be used for club play is shown on the ACBL General Convention Chart/MidChart/SuperChart.

From Duplicate Decisions:


NOTE: See the ACBL website for the Convention Charts ACBL has established for various levels of tournament competition. In general, clubs games are played under the ACBL’s General Convention Chart. Clubs may allow experimental conventions or agreements if they believe their particular club can handle them.

Law 40.B.2 also directly addresses this, recognizing club management as the “regulating authority.”

Clearly it is a two-way street. A club owner or manager or board may decide to allow a Mid-Chart convention in a regular club game as a way for players to gain knowledge about it and “test-drive” it. They are also completely within their rights to prohibit a convention like Suction in any seat, any auction, period. Restrictions or additions to the GCC should be posted at the club next to a copy of the GCC for all to see.

6.  Playing Suction in the allowed ways (such as over a strong 2♣ opening bid) on the GCC would not require a written description of the system nor a pre-alert. Playing Suction, if approved by the regulating authority whether it is a tournament sponsor, or a club manager, as a direct overcall of 1NT would require both a written description and a pre-alert. The ACBL does not require a written defense to this system.

“When using a method permitted by the Mid-Chart but not by the General Convention Chart, a pair is required to:

1. Pre-Alert the method(s)

2. Have a written description of the method(s) available for the opponents.

3. Except for those methods authorized by sections #1 – 5 below, have a copy of the approved suggested defense available for each opponent.” 

(Suction falls within #1-5, and requires no written defense.)


Online Resources

Laws of Duplicate Bridge 

Duplicate Decisions 

General, Mid-Chart, and Super Chart Conventions 

Alert Chart 

Alert Procedures