If you had shares of Sask Pool from days gone by, you might have sold them at a great loss. You can carry that loss forward, but need to document it and send the numbers to Canada Revenue Agency. Here is how the numbers work in my head:
1) Shares purchased at $12 (1000 shares cost $12,000).
2) Shares dropped to 30 cents or so and then reverse split one for 20 so the value became $6. If you sold those shares around that time ($6 or so) you really sold them for around 30 cents per, in other words those original 1,000 shares brought in only $300. That means you have a capital loss of $11,700 per 1,000 shares. A lot of farmers had well over $100,000 worth of deferred dividends with Sask Pool and many received at least 10,000 shares. If they held them until Sask Pool bought them back, the loss carried forward would be $11,700 x 10 = $117,000 worth of capital losses.
My numbers here might be a little off because I am working from memory and I never owned shares in SP. But you get the idea. Talk to your tax professional about this if it sounds like something you need to manage.