This convention is alertable.
Bergen raises are conventional raises of a 5-card major suit opening. After a 1♥ or 1♠ opening, a 3♣ response shows 4-card minimal support, while a 3♦ response shows 4-card invitational support. It is usually played with Jacoby 2NT.
Bergen raises are developed as an application of the law of total tricks, which indicates that one should compete at the 3-level with 9-card trump fit regardless of strength.
|5-card support||raise to 4||3♣||3♦||2NT|
|4-card support||raise to 3|
|3-card support||Pass||raise to 2||bid another suit then rebid the major|
- 3C minimum raise (7-9 points) with at least 4-card support. This response is alertable.
- 3D: invitational raise (10-12 points) with at least 4-card support. This response is alertable.
- 3 of the major: preemptive raise (0-6 points) with exactly 4-card support. This response is alertable in ACBL regulations.
reverse Bergen raise Edit
- ↑  Responses to One-Level Opening Suit Bids : Three-level jump raises not in competition which promise less than invitational values
Single raise - Jump raise
- The bidding is pushed to the 3-level whenever a 9-card fit is found, therefore, the opponents are very difficult to enter the bidding at this stage.