Deterministic Bitcoin Commitments - DBC

For RGB commitment operations, the main requirement for a Bitcoin commitment scheme to be valid is that:

The witness transaction must provably contain a single commitment.

With this requirement, it is not possible to construct an "alternative history" related to client-side data commitment in the same transaction. Thus, the message around which the single-use seal is closed is unique. To meet the above requirement, regardless of the number of outputs in a transaction, one and only one output is valid for each commitment scheme (Opret and Tapret):

The only valid outputs that can contain an RGB message commitment are:

1. The first output OP_RETURN (if present) for the Opret commitment scheme.

2. The first taproot output (if present) for the Tapret commitment scheme.

It is worth observing that a transaction can contain both a single Opret and a single Tapret commitment in two separate outputs. Due to the deterministic nature of the Seal Definition, these commitments will commit to different client-side validated data which, as we shall see later, explicitly indicate the commitment method used to refer to themselves.

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