This case, which is about software royalties under the Canadian double tax agreement, makes 4 key points – (1) take a ‘holistic’ approach to DTA interpretation2; (2) give primacy to the written text; (3) context, object and purpose ‘must also be considered’3; and (4) the OECD commentary and related materials should always be consulted4.
In short, we should interpret DTAs a bit more liberally than domestic tax legislation5. iTip – a good place to start in determining the domestic effect of a DTA is to understand the deeper trans-national principles on which it is based.
This case is from Episode 3 of interpretationNOW!
3 Arts 31 & 32 of the Vienna Convention on the Law of Treaties  ATS 2.