If your spouse is claiming 100% of any T-slips you have as joint investments, you need to enter them on their return.
If an investment slip is issued in both spouse's names, but one spouse contributed 100% of the funds to that account, you need to put it on that spouse's tax return even though the SIN on the slip may be for the spouse who is claiming "0%".
Just remember the "attribution rules": According to CRA Attribution rules, what you need to do is determine who contributed to the investment and what percentage. You report the interest earned in the same proportion as the funds that were contributed into the account that earned the income. So if these were "your" funds, then you would claim the income on the T3 & T5 slips 100% in your name.
You cannot change the amounts strictly for tax advantages, and you should continue to report it with the same percentages each year, as changing this each year can trigger a review and possible reassessment from CRA. Generally spouse's claim 50/50.
