From: http://www.tmxmoney.com/en/research/glossary.html

Board Lot
A standard trading unit as defined in UMIR (Universal Market Integrity Rules). The board lot size of a security on Toronto Stock Exchange or TSX Venture Exchange depends on the trading price of the security, as follows:

• Trading price per unit is less than $0.10 - board lot size is 1,000 units
• Trading price per unit is $0.10 to $0.99 - board lot size is 500 units
• Trading price per unit is $1.00 or more - board lot size is 100 units