Defensive publication is an intellectual property strategy designed to prevent other companies from acquiring patents on the technology. In these cases, the company making the publication wishes to be able to continue the use of the technology or invention but does not want to patent the technology or invention. They are not concerned in this case about other people implementing these inventions or the invention entering the public domain.
Prior art is the cornerstone of the patent process. Patents will only be granted if prior art cannot be found. If someone seeks a patent and prior art is found, then the invention they are trying to patent is not new and therefore their patent application would be denied. For example, imagine someone applies for a patent on the wheel. The patent examiner would very easily find lots of prior art of the wheel, therefore this patent would not be granted.
The creation of prior art is defensive publishing. This can take many forms as long as there is an enabling disclosure in the prior art. A defensive publication can be a document, demonstration, or series of pictures.
For your prior art to count and your invention to be considered published in the public domain, it needs to have an enabling disclosure. The invention must be explained in sufficient detail that someone skilled in the art can make and use the invention. Therefore, a demonstration of a new piece of technology should be accompanied by a level of explanation that will enable someone skilled in that field to produce and make the invention.
If the invention is not entirely disclosed, then this is not prior art and could leave the door open for another company to patent the same or a similar invention.
Why Make Prior Art?
Let’s say a company wishes to make a new kind of cleaning cloth for domestic use. They decide that they want to add natural fragrance to the cloths to make them more appealing products. They could patent the new invention, however, it would be very easy for another company to come up with a similar idea and patent that. Perhaps they could make subtle fragrance cloths.
In this case, the company has used their research and development department to make the new cloths. The expected return on having a monopoly is not very large. It would probably not cover the cost of patenting. Therefore the company can make a defensive publication of the invention. In fast moving technologies, the race to prior art can be much more important than the race to a patent.
Defensive publication protects companies against an aggressive move. If a rival patents a natural fragrance cloth, they may do so solely to disrupt a competitor. Without prior art, the company could end up not being able to sell the product in the marketplace. A rival company might see the cost of a patent as worthwhile if it takes down one of their competitors.