Documents filed to Companies House show the presenter was given more than 50 percent of the firm on February 26.
The listing shows that it is late in filing accounts for 2019 due to Derek’s ongoing illness.
In 2018, the company, set up in 2011, appeared to be taking in a healthy income.
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The mother-of-two added she worried she may sound like she’s “pleading poverty” but said she has had to rely on their friends for financial support during the difficult time.
Addressing further difficulties, Kate added she also couldn’t access her spouse’s bank or credit card accounts, their joint savings, or refinance the mortgage.
Giving an example of how this had been a problem, she said she was charged nearly £900 by a mobile provider when the family needed replacement handsets last year.
She added she also doesn’t have the legal right to see his medical notes, owing to data protection.
Kate went on to say she and her husband had discussed appointing the power of attorney in case anything happened, but said this isn’t logged anywhere.
The mother-of-two gave fans an insight into Derek’s health ordeal and her family’s experience in ITV documentary Finding Derek.