The different between First to File and First to Invent System

To identify the different between these two systems, first we have understand that there are three important dates in the process of patenting an invention to consider.
1. The date that the inventor first conceived of the completed invention.
2. The date that the inventor built a working model.
3. The date that the inventor filed a patent application.

In the “First to Invent” system, when the inventor complete these three step. The date that the inventor has done the first step would be “priority date” so long as the inventor does not abandoned, suppressed, or concealed the invention according to title 35 of the United States Code section 102 (g). If there were two inventors file the patent for the same invention, the inventor who first conceived of the invention would entitle to a patent.

For the “First to File” system, the last step would be the most important because the investor who file the patent first would entitle to a patent according to Thai patent law which it also use this system. If there were two investors file the patent for the same invention, the first one who file will be entitle to a patent. The problem only occur when two investor file the patent on the same date, even in different time. Those two shall agree whether a patent should be granted to one of them or all of them jointly. If no agreement has been reached within the period prescribed by the Director-General, they shall bring the case to the court according to Patent Act of Thailand B.E. 2522 section 16.

References
Title 35 of the United States Code section 102 (g)
Patent Act of Thailand B.E. 2522 section 16
http://www.generalpatent.com/first-file-vs-first-invent-who-really-benefits-changing-u-s-patent-system
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