Abandonment occurs when a patent or trademark right owner either explicitly (in writing) or implicitly (due to inaction) relinquishes his/her patent right.
Common examples of abandonment by inaction include when the United Stated Patent and Trademark Office (USPTO) fails to receive a response to an Office action from a patent applicant within 6 months from the date the Office action letter was mailed; or when the USPTO does not receive a statement of use (or request for an extension of time to file a statement of use) from a trademark applicant within 6 months from the issuance of a Notice of Allowance. Applications abandoned for failure to respond to an Office Action or to a Notice of Allowance can be revived or reinstated under certain circumstances.
The USPTO declares a patent “abandoned” or a trademark application “dead” when they are no longer pending. Abandonment may be of either the invention or the application. An abandoned application, per 37 CFR §§ 1.135 & 1.138, is one which is removed from the Office’s docket of pending applications.