At 10:46 a.m. EST (1546 GMT), the Toronto Stock Exchange's S&P/TSX composite index rose 0.1 of a point to 16,371.65. It touched an all-time intraday high of 16,404.12.
The heavyweight financials group rose 0.5 percent as bond yields climbed after data showing a stronger-than-expected gain in US private employment. Manulife Financial Corp advanced 1.5 percent to C$26.56.
Higher yields reduce the value of insurance companies' liabilities and increase net interest margins of banks.
Industrials firmed 0.3 percent, with Waste Connections Inc up 1.2 percent at C$87.86 after two analysts raised their price target on the stock.
The biggest gainer on the index was Prometic Life Sciences Inc , which rose 8.5 percent to C$1.53.
Six of the index's 10 main groups were lower.
The energy group, which had rallied as much as 11.9 percent since mid-December, fell 0.7 percent. Encana Corp was down 2.3 percent at C$16.91.
US crude prices were little changed at $61.66 a barrel.
The largest decliner on the TSX was Aphria Inc, down 10.3 percent at C$19.25. Another marijuana producer, Canopy Growth Co, fell 9.9 percent to $32.34.
The US Department of Justice on Thursday will rescind an earlier marijuana policy under former Democratic President Barack Obama that eased enforcement of federal laws amid a growing number of local legalization efforts, according to a source familiar with the change.