The IDS (or information disclosure statement) is a disclosure of the prior art that you or I are aware of, and any information you know of that may affect the patentability of the invention. Keep in mind that prior art is not limited to US patents. It can include foreign patents, patent applications, as well as non-patent literature including publications like scientific journal articles and evidence of sales or public use. These citations also do not need to be novelty-destroying. They need to be information that a reasonable Examiner would consider important when deciding whether or not to reject a patent application.
We are obligated, as inventor and patent practitioner, to disclose everything we know of the prior art to the USPTO according to 37 CFR 1.56. It is the responsibility of everyone associated with the patent to disclose information, and in most cases, the more you disclose, the better. A thorough disclosure of the prior art will improve your credibility and show to the Examiner that you’ve done your due diligence. This also gives the Examiner some guidance when he is making his own search, which can provide for a more streamlined, efficient examination process. The Examiner will then make his own evaluations of the information disclosed in your IDS, and decide which citations count as appropriate prior art for the patent application.
Also, a rejection based on any prior art that you disclose cannot be made final. This essentially means you won’t need to pay $600 in government fees to restart the examination process, called a Request for Continued Examination.
Furthermore, part of the valuation process of a patent involves an examination of the “references cited” portion of a patent. For example, this patent has 720 patent citations. This patent is used by United Video Properties Inc. to license remote program guides and is part of a compendium of patents and other IP that have been leveraged to make billions of dollars over the years.
Needless to say, in most cases it is not necessary to conduct a search to disclose 700 references. We are only tasked to disclose what we know. A company like United Video Properties is in the business of using patents to grow their monopoly, so they can probably cite a lot of known prior art from around the world. In a US patent application it is not a requirement for each applicant to have done a prior art search, but thorough information disclosure can be a marker of a strong application. Thorough information disclosure is a result of teamwork between the patent applicant and the patent practitioner. Let your patent agent/attorney know of any prior art references you find, so that proceeding toward filing IDS can be done in a timely and efficient manner.
The IDS can be filed at any point in the application process, starting from the filing of the patent onward all the way up to acceptance if you learn of any potential references. It is common to file more than one IDS per application. Filing the IDS is free if filed within 3 months of filing the application, before issuance of an Office action, or if the references were disclosed in a related non-US patent application. Otherwise, there is a small fee that must be paid to the USPTO when filing an IDS.
So not only is the IDS a statutory duty for all individuals substantively involved in the patent application process, it is a beneficial institution both for the applicant and the Examiner. The Examiner’s search burden is eased, the applicant benefits from improved ethos with the Examiner, and the applicant gets a discount for when he/she needs to extend the examination process. Moreover, a patent citing numerous references will be more likely to withstand challenges during litigation.