Patent pending

"Patent pending" (sometimes abbreviated by "pat. pend." or "pat. pending") or "patent applied for" are legal designations or expressions that can be used in relation to a product or process once a patent application for the product or process has been filed, but prior to the patent being issued or the application abandoned. The marking serves as a warning to the public, business, or potential infringers who would copy the invention that they may be liable for damages (including back-dated royalties), seizure, and injunction once a patent is issued.

Usage of the designation “patent pending” does not differentiate between examined and unexamined applications, nor between pending provisional applications and pending non-provisional applications. As a result, third parties may be unable to assess whether a pending application has undergone any substantive review or whether its claims are likely to mature into enforceable patent rights. The uniform usage of the designation across different procedural stages can obscure meaningful differences in legal posture associated with various types of patent filings. The “patent pending” designation also does not provide information about the scope, breadth, or validity of any claims that may ultimately issue. Because claims are typically amended during examination, third parties cannot reliably determine what subject matter may eventually be protected based solely on a pending application. This uncertainty can contribute to both overestimation and underestimation of the legal significance of “patent pending” status.

Fraudulent use of a patent pending designation is prohibited by the law of many countries and inventors should be cautious when marking products or methods that may arguably not be covered by any pending patent application. In some jurisdictions, such as the United Kingdom, a warning notice should ideally mention the number of the pending application.