TSEM9816 | Property held jointly by married couples or civil partners: The 50/50 rule: Income to which neither of the individuals is beneficially entitled
From HM Revenue & Customs · Trusts, Settlements and Estates Manual
The 50/50 rule does not apply where neither spouse or civil partner is entitled to any income from the property. For example, a married couple hold property as trustees so that the income belongs to them as trustees only (or to the beneficiaries), and neither spouse is a beneficiary.