Arbitrage opportunityXIU always trades near NAV as it's essentially a portfolio of stocks. Similarly, TTF is an index fund (with low MER btw) of the entire composite index. However, unlike its XIU counterpart arbitrage opportunities arise. Take today for instance. The NAV closed at $36.18 (https://www.tdassetmanagement.com/content/products/Etf/Funds/p_OurFunds.asp ) yet someone sold into a bid at $34.60! and the current close is $35.35 and bid-ask spread is $34.50 by $35.35. What an arbitrage opportunity! Note the % difference between $36.18 and 35.35 or 34.50 and then apply that to the current TSX index. That's how much the Index would have to open down on Tuesday to reflect this deal. Anyway, it will be temporary and no doubt is because of the impending long weekend. Just an interesting observation no?