User:Brian/Bridge/Subsequent bidding after an inverted minor raise

Inverted minors is a system in which a single raise of opener's minor is strong while a jump raise is weak. That is, 1♦ - 3♦ shows a weaker hand (on responder's part) than 1♦ - 2♦. This is the opposite of major suit raises, where a jump raise is stronger than a single raise.

The reason why many partnerships play minor raises inverted is that minor suit contracts are not actually the most desirable. Even with a minor suit fit, notrump is often preferable. By making the strong raise only a single raise, bidding space is conserved so the partnership can figure out whether or not to play in notrump. Specifically, a raise of the minor implies that no major suit fit can exist, so the minor suit and notrump are the only two options. With stoppers in all suits, a 3NT game is preferable to a 5m game, since making a 5m contract requires additional strength. Therefore, following an inverted minor raise, one partner or the other usually initiates stopper-bidding to determine whether notrump is viable.

Meanings of subsequent bids

If you are opener, you must alert your partner's raise.

After a double raise by responder, you should pass. Remember that a double raise can be made with a very weak hand. If you think 3NT is worth investigating now despite partner's potentially very weak hand, shouldn't you have opened 2♣ or 2NT originally instead of 1m?

Opener's rebids after a single raise

If...	then...
I have a minimum (12- HCP), and partner is a passed hand	Pass. Some partnerships have an agreement that the single raise is one-round forcing, but in this particular circumstance it really makes no sense to continue bidding—with a minimum hand opposite an invitational hand, 3NT is out of the picture, and rebidding 3m has no potential upside, not even preemptive value given that both opponents have passed.
I have a minimum (12- HCP), and partner is an unpassed hand	Rebid 3 of your minor. (Since 2NT has now been bypassed, any subsequent stopper-showing bid by partner indicates enough strength for 3NT.)
I have 13–14 HCP with stoppers in all side suits	Bid 2NT. Partner will sign off in either 3m or 3NT depending on strength.
I have 15+ HCP with stoppers in all side suits	Sign off in 3NT.
I have extra strength (15–18 total points) with a void or small singleton in a side suit and stoppers in the other two side suits	Make a splinter bid. Exception: avoid splintering in clubs since bidding 4♣ makes it impossible to sign off in 3NT.
I have a maximum (19+ total points)	TODO: how to do minor-suit slam bidding?
I have a side suit stopper but I don't have all three side suits stopped.	Initiate stopper-bidding as described below.
Otherwise (I don't have any side suit stoppers)	(TODO: Can responder make an inverted minor raise if they have all three side suit stoppers?)

Responder's rebids

If...	then...
Partner rebid 3NT after my raise	Pass.
Partner rebid 2NT after my raise and I have 12+ HCP	Raise to 3NT, since partner's 2NT rebid shows 13–14 HCP.
Partner rebid 2NT after my raise and I have 11- HCP	Sign off in 3m.
Partner bid a new suit after my double raise	See below on how to participate in stopper-bidding.
Partner jump-shifted after my single raise	This is a splinter bid; respond accordingly.
Partner bid a new suit after my single raise	See below on how to participate in stopper-bidding.
Partner rebid 3m and I have 14+ HCP with all the side suits stopped	Sign off in 3NT.
Partner rebid 3m and I have 14+ HCP with at least one side suit stopped	Initiate stopper-bidding (see below).
Partner rebid 3m and none of the above are true	Pass. (TODO: What if responder has slam interest?)

Stopper-bidding sequences

In order to determine whether a notrump game is advisable, partners bid stoppers up the line. Once stopper-bidding has commenced, rebids by either partner are as follows:

If...	then...
My partner returned to the agreed minor	Pass. Partner is telling you that the partnership is missing one or more side-suit stoppers so you do not belong in notrump.
My partner bid 2NT, but I know that we have enough strength for game.	Raise to 3NT, since partner's bid of 2NT means they believe all side suits are stopped.
My partner bid 2NT, but I don't have enough strength to force to game.	Sign off in 3 of the agreed minor.
My partner bid a side suit, bypassing a suit in which I also have no stopper. (For example, 1♣ - 2♣ - 2♥ denies a diamond stopper.)	Sign off in the agreed minor at the cheapest available level, since partner has just denied a stopper in the bypassed suit.
My partner bid a side suit and I now know that we have all suits stopped.	Sign off in 3NT if you know the partnership has enough strength; otherwise bid 2NT. Partner's subsequent raise to 3m or 3NT is to play.
My partner bid a side suit, I have game-forcing strength, and I don't yet know whether all suits are stopped.	Bid the cheapest available suit in which you have a stopper you haven't shown yet, letting partner you have that suit stopped.
My partner bid a side suit, I don't yet know whether all suits are stopped, and I also don't know whether we have enough strength for game.	Bid your cheapest available stopper if you can do so without bypassing 3m. If you cannot do so, then sign off in 3m.