A defensive publication, or defensive disclosure, is an intellectual property strategy used to prevent another party from obtaining a patent on a product, apparatus or method for instance. The strategy consists in disclosing an enabling description and/or drawing of the product, apparatus or method so that it enters the public domain and becomes prior art.Therefore, the defensive publication of perhaps otherwise patentable information may work to defeat the novelty of a subsequent patent application.

One reason why companies decide to use defensive publication over patents is cost. In the United States, for example, to obtain a published patent application, one must incur at least filing fee, examination fee, search fees, and early publication fees, and meet the filing requirements for a proper patent application.

“The defensive publication route is especially useful for innovations that do not warrant the high costs incurred in patent applications but to which scientists do want to retain access.

Siddhast Provide defensive publication service via e-notary.in ,

Method of publication	Cost	Retrieval probability by patent examiners	Certainty of publication date	Robustness	Cons
e-notary	$100(Max 100 pages)	Medium *	High Timestamped contents	High	None
Web page	Free	Medium	May be questioned	Low Only one version is published	Free but limited
Online publishing	90$ per page	Medium	High	Only one version is published	Very expensive and not robust.
Patent application (early publication, i.e. published rapidly after filing)	$100  – $200 (filing and publication fees)	High	Date is certain	Only one version is published	Formal matters to comply with before patent offices. Delays.