Ignore my previous comment...I figured out my issue and I don't think it's the same as yours after all. I will say that this is extra confusing when the spousal split and the tax inclusion rate are both 50%.
The answer to the question of whether or not you can split your capital gain with your spouse depends on whether or not you shared in the purchase of the investment in the first place and how much your spouse contributed. Can I Split My Capital Gain With My Spouse?
Thank you for choosing TurboTax.
What proof is required by CRA to demonstrate that both spouses contributed to an investment. Let's say that I handle most of the investing from my account, but my spouse takes an equal amount of money to fund household expenses. It is all part of one shared pool and allocated for efficiency, but does not demonstrate direct link between the spouses funds and the investment.
@mattrrr If your spouse contributed to the investment their would a record of wither them directly depositing money into the investment account, or them transfering money to you so you can invest it on their behalf.