This standard is an amendment of IEEE Std 1588™-2019. Updates to various sections to correct text, make clarifications, and other improvements are provided in this amendment.

This amendment will improve the terminology in the standard, and more completely specify the behavior of the protocol, in the following ways:-Clarification of the term "retransmit"-Elaboration of how type-length-value (TLV) message extensions are handled by Boundary Clocks and Transparent Clocks-Fix editorial errors and clarify unclear statements.