Some players agree that when you bid 4♣, it is always Gerber (asking for aces).
Gerber, named after its inventor, John Gerber, is a convention used to ask for aces (or key cards if you and partner agree on that). In traditional Gerber, responder to the convention bids 4♦ to show four aces or no aces, 4♥ to show one, etc.
So, when is 4♣ Gerber, and when is it something else? Read on.
You are lucky enough to pick up this nice hand:
♠ A K 9 8 5 4 3 ♥ K 8 ♦ — ♣ A K Q 6
The auction, with no one vulnerable, starts smoothly.
2♣ is your strong bid. Partner’s 2♦ is a waiting bid. You do not know what North has at this point, but you do not have to worry yet that he is broke. He may have quite a few points for you.
There is no need to jump on the second round of bidding. You expect to play in spades, but if North hates them and has some clubs, getting to a club contract could be best. You want to keep bidding room so as to explore all your options.
What do you do after partner raises to 3♠? Do you ask for aces with 4NT?
That would be awful. If North has two aces, you can bid 7NT, but if he has one, you have no idea if it is the ♥A or the ♦A. If he has the ♥A, you want to be in 7♠. If he has the ♦A, you best stop in 6♠.
Do you ask for aces with 4♣, the Gerber convention?
Hopefully, you do not choose this bid. If you play 4♣ as asking for aces, you run into the same problems that the 4NT bidders do.
Do you make a cuebid of 4♣?
This is not a 4NT hand and it is not a Gerber hand. It is a cuebidding hand. And that is the point of this example hand.
I know of some players who use 4♣ as Gerber whenever it is bid. This is a waste of a good bid. 4♣ can be used for many things on many auctions and if you use it as asking for aces, you will lose out on a lot of hands where 4♣ could be used as something else.
Here are the first of 10 auctions where partner bids 4♣ (the rest will be covered next week). What do you think partner means? Your partner is South and you are North.