ASSIGNMENTS OF PATENT RIGHTS. A Brief Description of the Procedure in the Recording of BY WILLIS B. MAGRUDER, CHIEF OF ASSIGNMENT DIVISION, U. S. PATENT OFFICE. COPYRIGHT, 1912, WILLIS B. MAGRUDER. PREFACE. As Chief of the Assignment Division of the United States Patent Office, inquiries are often propounded to me relating to assignments, the recording thereof, and the effect of certain rights granted under patents and applications for patents, and in order to answer them intelligently it has been necessary to search many works of reference, as well as to rely upon my experience of nearly thirty years in the Assignment Division. The solicitation of a number of Attorneys has prompted me to publish this pamphlet, with the hope that it will prove of value to all interested in title matters pertaining to patent property. Washington, D. C., January, 1912. WILLIS B. MAGRUDER. 13 Assignments of Patents. Section 4898 of the Revised Statutes provides that: "Every patent or any interest therein shall be assignable in law by an instrument in writing; and the patentee or his assigns or legal representatives may, in like manner, grant and convey an exclusive right under his patent to the whole or any specified part of the United States. An assignment, grant or conveyance shall be void as against any subsequent purchaser or mortgagee for a valuable consideration, without notice, unless it is recorded in the Patent Office within three months from the date thereof." RECORD BOOKS. In order to comply with said law the Patent Office has provided books for the record of such assignments as may be presented, and the assignment records of the Patent Office are intact from 1837 to the present date. In 1836 the entire records of the Patent Office were destroyed in a fire, and that is the reason why the records of assignments prior to 1837 are not in existence. The books provided for the record of assignments are designated "Transfers of Patents," and contain 500 pages each, in alphabetical series, numbered from 1 to 88, and therefore the designation where an instrument is recorded is referred to by letter and number, as, for example, Liber H 77; W 76; or A 75, etc. Since 1837 to the present date there are over 2,300 of these record books. It would therefore be an endless task to make a search of these volumes to ascertain the title to a patent; so it was necessary to have a separate index in which searches could be readily made, and such books were provided and designated "Digest of Assignments," in which there is an index of each instrument under the name of the inventor only, and consequently it is necessary to know the |