David M. Kleiman
U.S. Patent Attorney

21900 Burbank Blvd.
Third Floor
Woodland Hills, CA 91367
Tel: (818) 884-0949
Fax: (818) 332-4373

The Purpose Of Keeping A Witnessed Notebook

A properly witnessed inventor notebook can help you as an inventor properly document your inventive concept(s), and create a record of your efforts to reduce your invention(s) to practice.

The Physical Requirements of An Inventor Notebook

To best serve its evidentiary function an inventor's notebook should be in a form where it will be readily apparent that the contents have not been tampered with, such as having pages that may have been removed, replaced, or altered. Accordingly, an inventor’s notebook should:

      1. Be permanently bound with a fixed number of pages (no looseleaf binders);
      2. Have all of the pages sequentially numbered;
      3. Have space on each page for at least one witness to sign and date.

Correctly Using An Inventor's Notebook

Once you have a suitable notebook it is important that it be used, and used correctly, in order for it to serve its function of evidencing invention.

I. How To Write In The Notebook

a. You Should Be The Only One Using The Notebook
Other than having the notebook pages witnessed as discussed below, you should be the only person writing in the notebook. Record your name and contact information somewhere in or on the book to identify it as yours. It should also be clearly labeled as being confidential information.

b. Write Permanently & Legibly
All information placed in the notebook should be in permanent ink only (nothing eraseable), and should be clearly legible (so that a judge or jury could see and understand what has been written).

c. No Empty Spaces Or Skipped Pages
Don’t skip pages, or leave blank areas on a page. All text should be single spaced. Each page should be limited to entries from a single day for a single subject. Draw a large “X” through any remaining empty space on a page.

d. Permanently Attach Any Supplemental Materials
Supplemental materials such as photographs, graphs, or drawings should be in permanent ink, be placed in chronological order, be permanently attached to the page (e.g. by glue), and be labeled. Write next to all supplemental material a description of what it is.

e. Don’t Write About Different Inventions On The Same Page.
If you use your notebook to document multiple inventions, don’t mix information about different inventions on the same page: Make sure that when you use a page it only has information about one invention. Use a “continued from page” and “continued on page” reference on each page to connect together pages about an invention.

f. NEVER Make Alterations Of Any Kind
Never tear out pages, erase anything, or alter notebook entries. If you make a mistake while making an entry just draw a line through it so that the mistake is still readable, then date and initial next to the line. NEVER do anything to a page after it has been read and signed by a witness.

g. Don’t Record The Substance of Communications With Your Attorney
You may need to disclose your notebook contents to third parties, such as witnesses, a patent examiner, judge, or jury. To minimize the risk in such cases of waiving the privilege of confidentiality you have for communications with your attorney (which can be valuable in litigation over an invention), it is recommended that you generally avoid recording the substance of any communications you have had with an attorney in your inventor notebook. You can always keep a record of any such communications separate from the notebook if necessary.

A hypothetical example of a completed page in a witnessed inventor notebook is shown below:

II. What To Write In The Inventor Notebook

a. Your Inventive Concept
As soon as possible, describe in full detail what your invention is, and how you contemplate the invention could be made and used. Use both text and drawings if appropriate. Someone else in the area of technology for the invention should be able to clearly understand from your description what the invention is, and how you would make and use the invention.

b. Your “Reduction To Practice” Efforts
The act of invention is not legally complete until your invention has been “reduced to practice”. An invention is reduced to practice by either (1) filing a patent application, or (2) building a working prototype of the invention. Be diligent in your efforts to reduce your invention to practice by working in a continuous and reasonable manner to reduce your invention to practice with no large unexplained gaps of inactivity. Make regular and detailed entries in the notebook that describe what you are doing to reduce your invention to practice (e.g. ordering parts, conducting experiments, etc. . . ). Describe all the facts and circumstances of what you do, when you do it, and why you do it. Save any records related to your efforts to reduce your invention to practice (e.g. receipts, correspondence, test results). If you build a working invention have your corroborating witness(es) observe, in confidence, the invention working.


In the U.S. evidence related to invention may need to be corroborated. So it can be important to disclose your inventive concept and reduction to practice efforts in confidence to at least one independent witness who is not a co-inventor, and document this by having them sign your notebook.

a. Treat Your Inventor Notebook As Confidential
Treat your notebook as highly confidential. This is important to maintaining your rights. Do not disclose the contents of it to anyone, other than your attorney, unless they first agree in writing to keep the information confidential and not use it.

b. Make Sure Any Witness Used Is Qualified
Any corroborating witness must be a person who is not a co-inventor, is an adult, and who has the technical background to both read and understand your description of the invention. It is recommended that any witness used be someone who is credible, trustworthy, and of good character. Ideally they should not have a financial stake in the success of the invention, and not be an immediate family member. A witness should preferably be someone who you believe is reasonably likely to be available to provide testimony for you, if need be, many years after they witness your notebook.

c. Always Use A Written Witness Confidentiality Agreement
Before a witness reads any pages in the notebook with information about the invention, the witness should first read and sign a confidentiality agreement (also commonly referred to as a "non-disclosure agreement") where the witness promises to keep the confidential information disclosed to them a secret and not use the information. An example of a completed witness confidentiality agreement form, like that included in the Winning Inventor Notebook, is shown below:

Give each witness a copy of the completed confidentiality agreement that they have read and signed, and something of value (e.g. a dollar) in exchange for their agreement. Doing this helps to ensure that the agreement by the witness to keep your invention information confidential will be legally enforceable.

d. How To Have The Notebook "Witnessed"
After having signed a written confidentiality agreement, the witness(es) should read and understand the contents of each completed page in the notebook that has not already been witnessed. After reading the page they should sign and date (in permanent ink) a statement somewhere on the page indicating that they read and understood what was disclosed on the page on that date (see the sample hypothetical notebook page above).

e. Only One Witness Is Required, But Two Is Better
Using two witnesses increases the chances of at least one witness being available later if need be. However, one witness signing a page is sufficient.

Keep your witnessed inventor notebook in a safe place, and do not discard it even after you have filed a patent application and received a patent. Sometimes a witnessed inventor notebook will not be needed until years later.

IMPORTANT: Not A Substitute For A Timely Filed Patent Application
A properly maintained witnessed inventor notebook when used properly can be valuable. However, a witnessed inventor notebook is not a substitute for a timely filed patent application, and will not by itself give you any exclusive rights in an invention. Accordingly, if you do want to secure exclusive rights in an invention make full use of a witnessed inventor notebook but don’t unnecessarily delay in filing a patent application.