"One day son, all this will be yours!" maybe a tired, stereotypical (and probably outdated) phrase stated by a farming father to his son coming of age, standing on a hill overlooking his vast empire as the sun sets; but one which nonetheless may emphasize the family nature of farming and the lineage. An old adage is that you don't own the farm, you're just looking after it for the next generation like some family heirloom.

It is not an exaggeration to call the farm the family silver. But what if son stays on the farm, in anticipation of his inheriting it, but dad subsequently decides to do what Harold Macmillan criticized Margaret Thatcher for doing and starts selling off that family silver? Or, more likely, leaves it in his Will to someone other than his son.

The problem is that dad's earlier promise, on its own, isn't worth the paper it is written on. If dad were to die and leave the farm to his other children, or even the cats' home, he is entirely within his rights to do so as far the law is concerned. We have testamentary freedom in the UK, and provided all the formalities are met and one's faculties are in order you can leave what you like to whom you like upon death; we do not have forced heirship unlike in some European countries.

What remedy would son have in this case? Assuming the Will is in order there would be few options as far as the law is concerned. Any promise can be enforceable even if it's verbal (though this can be hard to prove, especially if dad is dead) if consideration is given by son in this case e.g. acting to his detriment as a result of that promise or made some other sacrifices elsewhere. All these are the ingredients to make an enforceable contract in English law. However, another ingredient of that is for there to be an intention to create a legal relationship – and a court would be unlikely to enforce this between father and son.

The only option left to son is the law of equity.

The concept of remedying the situation of someone going back on a promise, upon which someone has relied to their detriment, is nothing particularly new, but the phrase "proprietary estoppel" to name the principle to combat it, is relatively modern.

Lord Denning, the man who could turn dry legal terminology into near poetic prose gave a summary of proprietary estoppel in Crabb v. Arun DC (1976):

This is what son would rely upon to wrestle his inheritance (or part of it) back from the legatee. He would needed to have relied on his father's clear and identifiable promise (proving that alone might be an issue in face of a dispute!).

If he was going to stay on the farm anyway even without father's assurance, he would have no claim – there would be no causative link between the promise in question and his subsequent actions. In reliance on father's promise son would also need to suffer detriment of some sort – either in terms of actual cost, but also in terms of other things foregone. Son might have had an offer at a place at Harper Adams or Reading which he turned down to stay on the farm and build up his inheritance; he might even have had a training contract at Albert Goodman lined up!

He would have arguably given up wider opportunities as a direct result of relying on his father's promise. To right this wrong, the courts could impose an 'implied' trust onto the actual legatee for the beneficial ownership of son. However, as stated above the equity courts can do whatever they think fit to remedy the situation – a cash payment representing son's efforts and/or expected inheritance may be suitable. Such a situation happened concerning a farm near Yeovil in 2018.

The case of Habberfield v Habberfield concerned not son, but younger daughter, Lucy. Lucy claimed that father had promised her the dairy unit of the farm upon his retirement. Upon his death, he left the farm to his wife who then closed the dairy unit down. The wife had claimed that because of a family dispute, which caused Lucy to leave the farm just before father died, Lucy could not make a claim, despite her working on the farm for 30 years prior. However, in 2018 the High Court held that all the ingredients for a proprietary estoppel claim were in place for Lucy. An award of £1.17million was deemed the most suitable remedy and was awarded to her as the cost required to re-open the dairy unit and get her farming again. The Court of Appeal upheld this judgment in spring 2019.

Whilst farming is a family business and most of time it is without dispute and successions may be seamless, sometimes blood is not thicker than water. Death and vast fortunes do not always go well together and misunderstandings in life can make a difficult time even worse upon death. The lesson here would seem to be: clarity, proper lifetime retirement and succession planning, and having everything in the open – and in writing!!

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