I am the assigned Gen-ART reviewer for this draft. The General Area Review Team (Gen-ART) reviews all IETF documents being processed by the IESG for the IETF Chair.  Please treat these comments just like any other last call comments.   For more information, please see the FAQ at   < https://trac.tools.ietf.org/area/gen/trac/wiki/GenArtfaq >.   Document: draft-ietf-calext-extensions-03 Reviewer: Dan Romascanu Review Date: 6/21/16 IETF LC End Date: 6/22/16 IESG Telechat date: 7/7/16   Summary: A clear document, almost ready from the Gen-ART point of view. I recommend to clarify the two minor issues below before approval.   Major issues:   Minor issues:   1.        Should not this document be marked as ‘Updates RFC 5545’? The document recommends that all properties not defined in 5545 always include a “VALUE” parameter if the type is other than “TEXT” It also modifies some existing properties and defines new properties and elements that bring into the standard extension elements added by vendors into their specification. 2.        I had a hard time understanding some of the details in 5.7 (REFRESH-INTERVAL Property). These may be however due to my lack of familiarity with the style of iCal definitions and notations – so only explanations may be sufficient. First I do not understand what is covered under Property Parameters: what means ‘IANA and non-standard property parameters’ that can be defined here – and why here? Maybe an example would help. Second in the format definition: dur-value … consisting of a positive duration of time – should not units be specified here as well? Last, I did not understand VALUE=DURATION:P1W – maybe it’s just me missing the notation   Nits/editorial comments: