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For a call to specify a denomination, it should carry or impart information regarding the holding in that particular denomination. This can mean guaranteed length in a certain suit, or alternatively a control in a certain suit, or even shortage in a certain suit.
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In respect to Law 27B1(a), for partner not to be barred, the replacement call needs to specify the same type of feature in that same denomination.
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In respect to Law 27B1(a), for partner not to be barred, the replacement call needs to specify the same type of feature in that same denomination.
So it's not the denomination that was named in the bid, it's the denomination whose holding is being described. E.g. a transfer bid specifies the next suit, a Bergen raise or Jacoby 2NT specifies opener's suit. A splinter raise specifies two suits: length in partner's suit, shortness in the suit bid.