CAVEAT, kā’vē-ăt (Lat. “let him beware”), in law, a notice served on a public officer or court to refrain from doing a certain act without first giving notice to the caveator, as the person is termed who enters the caveat. Perhaps the best known use of the caveat in the United States is its entry by an inventor in the Patent Office for the purpose of establishing his claim to priority of invention, by enjoining its officers from issuing letters patent for any invention interfering with or infringing the rights claimed by the caveator without first giving him notice of the application for such letters patent. The terms of the caveat must set forth the claims of the inventor and the details of his invention with sufficient particularity to enable the officials of the Patent Office to determine whether a subsequent application for letters falls within the claims of the first inventor. If such is the case the caveator is entitled to notice of such interfering application, and the new applicant’s claim to letters is suspended for three months, during which period the caveator must complete his specifications and file his own application for letters patent. If no interfering application is filed, the caveator’s rights remain valid for one year, and may be renewed at the end of that term, for one year more, on payment of a second fee.

The law providing for the filing of caveats was repealed by Congress in 1910. Other uses of the caveat are to prohibit (without notice to the caveator) the admission of a will to probate, the enrolment of a decree in chancery, the grant of letters testamentary to an executor, the issuing of a commission de lunatico inquirendo, etc On the filing of such a caveat and due notice being served thereunder, a hearing is had before a competent tribunal for the determination of the rights in the matter. (See Patents). Consult ‘Rules of United States Patent Office’; Merwin, ‘Patentability of Inventions’ (Boston 1883); Luby, ‘Patent Office Practice’ (Kalamazoo 1897).

CAVEAT, kä’vē-ät, EMPTOR (Lat. “let the buyer beware”), a rule of law that warns the purchaser to take care and examine property before he buys it. In sales of real estate the purchaser’s right to relief depends on the covenants in the deed in the absence of fraud on the part of the vendor. In 1 Serg. & R. 42, the rule is stated as follows:

“The rule of caveat emptor strictly applies to the purchase of lands, and the consideration-money cannot be recovered back after a deed executed, unless in case of fraud, where some covenant inserted in the deed has been broken. The purchaser has it in his power to protect himself by proper covenants, and there is no reason why the law should provide to him a remedy, where he himself has been wholly inattentive and negligent in this particular.”

In sales of personal property the purchaser buys at his own risk, in the absence of an express warranty by the seller, or when the law does not imply a warranty from the circumstances of the sale or the nature of the thing sold, and when the seller was not guilty of a fraudulent misrepresentation or concealment. The purchaser must examine the quality of the goods bought and rely upon his own judgment. Generally, if the article purchased is defective, and an examination, such as a reasonable and prudent man would make, would enable him to see the defect, it is not a fraud on the part of the seller not to call his attention to it.

At common law in the city of London, the law of market overt applied to all stores where articles in that particular line were sold. The purchaser got a good title, but as to the quality the purchaser must examine and judge for himself.

SOURCE: The Encyclopedia Americana – Caveat 1920