implementor
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Implementors should treat Proposed Standards as immature
specifications. It is desirable to implement them in order to gain
experience and to validate ...
... defined here. National and international groups also publish
"implementors' agreements" that are analogous to Applicability
Statements, capturing a body of implementation-specific detail
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... claimed rights. Where implementations are required before
advancement of a specification, only implementations that have, by
statement of the implementors, taken adequate steps to comply with
any such rights, or claimed rights, shall be considered for the
purpose of showing the adequacy of the specification.
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... to obtain a general license or permission for the use of such
proprietary rights by implementors or users of this
specification can be obtained from the IETF Secretariat."
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