SOAML11 — Figure 40: Specification

Here <<specification>> is introduced and <<Participant>> is used on the implementation (realization). The relationship between <<specification>> and <<Participant>> is not clear to me in the specification. I would argue that a <<Participant>> can be seen as a logical system component that represents a specification, which can be further decomposed into a set of Participants (in the case you want to specify lower-level/participant-level services architectures) or components (design of software components).