Bidding in Third and Fourth Seats
When your partner passes as dealer and the next hand passes as well, things change. Whereas you would not consider bidding with a hand as weak as 10 high-card points in normal circumstances, you will often do so in third seat (that is, when your partner is the dealer).
The reason is that if you play a disciplined style with sound opening bids, partner will pass on occasion when she has a 12-point hand, and she will certainly pass with 10 or 11. If you hold a hand of 11 points yourself, you must consider that the majority of the high-card points could be with your side. That means you should be able to make something.
In essence, you are opening light in third seat as a way of “protecting” your plus score. This is more important in duplicate bridge than in party or rubber bridge, but it is a principle with which you should become familiar. Here are the basics:
Open light in third seat only with hands with which you will be comfortable passing whatever bid your partner might make. If you have a relatively balanced hand with 10 HCP and at least three-card support for all other suits, it's okay to open the bidding. Unless you are forced to bid, however, plan on keeping your mouth shut for the duration of the auction. If you have as few as two in some suit partner might bid, just pass. It will be bad for partnership harmony if you pass partner's bid and put down a dummy with only two trumps.
If you open the bidding in third seat and voluntarily bid again, it shows a full opening hand.
Bid the suit you want your partner to lead — and that means you can break the cardinal rule about opening a major suit with only four of them. Take this hand, for example:
This is a reasonable third-seat opener. You have only four spades, but do you really want your partner to lead one of the minors if the opponents compete and buy the contract? Bid your best suit. No matter what partner bids, you can pass.
When there are three passes to you, the situation changes yet again. If you pass, you will get no score. That's not great, but at least it's not a minus. Again, this is more important at duplicate, but the principle is good to know.
There is a time-tested way to determine whether to bid in fourth seat. It's called the Rule of Fifteen, and it's pretty easy. Simply count up your high-card points, then add that to the number of spades in your hand. If the sum is 15, open the bidding with whatever bid your system calls for. If the sum is 14 or less, pass it out.
A famous woman player from Great Britain had a somewhat different view of the Rule of Fifteen. Her view was that if the player in fourth-seat held a singleton or void in spades, that meant there was a fair chance partner had some spades, so she bid even when her hand didn't meet all the parameters of the Rule of Fifteen.
The reason spades figure into the equation is that it is the “boss” suit. The opponents may be light in values, but if they have the spade suit they can outbid you. If you hold extra strength or some length in spades, that lowers the chances that the opponents can get in there with the highest-ranking suit.
The Rule of Fifteen is a bit of an oversimplification, but in the main it is valid.