A more thorough explanation:

in fructu

In fructu means "among the fruit" in Latin. In legal terms, it refers to a situation where a person owns the fruits of something they possess, but not the thing itself. For example, if someone possesses a goat that they do not own, they are entitled to the goat's milk, wool, and offspring, but not the goat's meat.

If a farmer allows someone to use their land to grow crops, the farmer still owns the land, but the person who grows the crops is entitled to the fruits of their labor. This means they can harvest and sell the crops, but they do not own the land itself. Another example is if someone rents a house, they are entitled to use the house and enjoy its amenities, but they do not own the property.