The DDS standard states the criteria under which an implementation is compliant. Following is the excerpt:

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COMPLIANCE

The copyright holders listed above acknowledge that the Object Management Group (acting itself or through its designees) is and shall at all times be the sole entity that may authorize developers, suppliers and sellers of computer software to use certification marks, trademarks or other special designations to indicate compliance with these materials. Software developed under the terms of this license may claim compliance or conformance with this specification if and only if the software compliance is of a nature fully matching the applicable compliance points as stated in the specification. Software developed only partially matching the applicable compliance points may claim only that the software was based on this specification, but may not claim compliance or conformance with this specification.
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At a minimum, to be compliant, an implementation must:

(1) Implement the Minimum profile.
Meaning the middleware shall offer and implement all the specified DDS entities, with should the specified function calls and parameters, and also offer all the specified QoS policies with the specified parameters and behaviors.

(2) Support the programming API obtained from the IDL provided as part of the DDS specification.
The IDL to programmling language mapping (C, C++, Java, etc.) are also specified by OMG standards.