Hummels Wharf Landlord-Tenant Lawyer, Pennsylvania

A legal doctrine stating that if a person receives money or other property through no effort of his own, at the expense of another, the recipient should return the property to the rightful owner, even if the property was not obtained illegally. Most courts will order that the property be returned if the party who has suffered the loss brings a lawsuit.

Principles of international law so fundamental that no nation may ignore them or attempt to contract out of them through treaties. For example, genocide and participating in a slave trade are thought to be jus cogens.

An agreement, generally included in an employment contract or a contract for the sale of a business, where one party agrees not to compete with the other party for a specific period of time and within a particular area. Salespeople, for example, often sign noncompetition agreements that prevent them from using the contacts gained by one employer to benefit another employer. Or a salesperson may sign what is known as a 'noncompete,' agreeing not to sell within a particular area, or even work in the same type of business. In some states, such as California, courts view noncompetition agreements with disfavor and will not enforce them unless the restrictions are very narrow. In other states, courts routinely uphold them.

A means by which one can legally take another's property without paying for it. The requirements for adversely possessing property vary between states, but usually include continuous and open use for a period of five or more years and paying taxes on the property in question.

A doctrine that prevents a defendant from re-litigating an issue after it has been lost. For example, if your neighbor sues you for putting up a fence on his land and the court rules that your fence extends beyond your property line, you can't later file your own lawsuit seeking a declaration that the property line is incorrectly drawn.

For income and capital gains tax purposes, the value that is used to determine profit or loss when property is sold. Often the basis is what you paid for the property, 'adjusted' to reflect improvements made or damage incurred while you own the property. See stepped-up basis, carryover basis.

A provision in a deed or will that attempts to restrict ownership of the property -- for example, selling your house to your daughter with the provision that it never be sold to anyone outside the family. These provisions are generally unenforceable.

A phrase used in property law to describe a right or duty that remains with a piece of property no matter who owns it. For example, the duty to allow a public beach access path across waterfront property would most likely pass from one owner of the property to the next.