Sophie Heawood: There's no anti-men law that I can see

It's not every day that the fate of a modest Essex bungalow becomes a matter for a county court judge, then the Court of Appeal, and then the Supreme Court. Yet one disgruntled couple have taken a dispute over their home's ownership that far – and the outcome may prove a landmark in any future bickerings involving unmarried pairs. Especially as the bloke in the case is claiming that his ex-partner only won it because she's a woman.

Ice-cream salesman Leonard Kernott and his then girlfriend Patricia Jones bought the property together in 1985, with a £6,000 deposit gained from the sale of her previous home. After they split up, he moved out and she paid the mortgage by herself for 13 years. Now their children have grown up, he wants half the value of the house – but the Supreme Court says he is only entitled to a tenth.

It has to be said, this bloke is hardly throwing his weight about – he speaks rather sensitively about the breakdown of their relationship, explains how he renovated the house himself, and says he personally only ever hoped for 25 per cent, not half.

But he is not happy with his 10 per cent tithing at all, and falls into the last refuge of a scoundrel when he claims that "it feels like the law will always side with the woman". It doesn't take a huge grasp of maths to see that the law here is hardly siding with the person who is female, so much as with the person who bought it and paid for it and raised children in it and lives in it.

Yet Mr Kernott is not alone in his convictions. Take a look at the Fathers 4 Justice website and you'll see how they feel their voices have still not been heard. (They describe The Family Justice Review, the far-reaching report on family law that was published this month, as a "monstrous sham", for one.)

Yet when I recently registered the birth of my child, the registrar turned to the baby's dad and said that even though we weren't married, he would still have equal parenting rights if he went on the birth certificate, and that this law had only come into effect this year. "You've got Batman and Robin to thank for that," she laughed, referring to the Fathers 4 Justice campaigners. "Why is it," she continued, "that they make such a fuss about their demands, but hardly mention it when they've been met?"

Divorce cases where ex-wives get big payouts always make the headlines, but they reflect a growing trend to recognise non-financial contributions to a marriage with financial remuneration. When, in a celebrated case in 2004, the footballer Ray Parlour went to court with his wife, she was controversially awarded a third of his future earnings. But then she had contributed to his success. She had earned her reward even though she had never kicked a ball. That's something Leonard Kernott might like to think about.