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Would you happen to know if your ex partner ever registered an interest on the Land Registry Deeds to your property (normally called a Restriction) to protect his financial interest?
Well, there is no legal obligation on you to repay the deposit to your ex partner, on the basis that no agreement to do so was ever signed by you.
Likewise, as your ex partner has not registered any interest against the property, you are free to sell it and your ex partner would not even know that you had sold.
I hope this assists and clarifies the legal position.
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