Patent grace periods
If patent protection for an invention (i.e. new product or process) is of interest, the invention should be kept secret until a patent application is filed, although grace periods available in some countries may help if an invention is ‘published’ prematurely.
The general rule
As a general rule, a patent cannot validly cover anything that was publicly known before its priority date. ‘Publicly known’ takes in everything that is not secret – it is enough if one person not bound by confidentiality has access to details of the invention. The ‘priority date’ of a patent is usually the filing date of the first patent application leading to the patent.
Exceptions to the general rule
Twelve month grace periods available in Australia, New Zealand, the US, Canada and a few other countries provide exceptions to this general rule that can allow you to pursue patent protection if you have not kept the invention secret.
Significant limitations
The grace periods have significant limitations and so should be viewed as backup in the case of accidental publication, rather than relied on as a matter of course. Patent protection will not be possible if others independently develop and go public with the same invention before your patent application is filed (aside from some rare exceptions). Most jurisdictions do not have grace periods. In particular, Europe does not have a grace period.