http://www.uspto.gov/web/offices/pac...ex.html#patent
20 year utility patents are not renewable Robert.
They can be extended if you have additional improvements that are recognized as novel above the original patent. That would be a new patent with a new assignment number IE patent number.
Prototypes are not necessary. I have one being issued and no prototype was ever requested or provided, however mine is a design patent which has a shorter term.
Utility patents time period begins when the complete application is filed, while Design patents time period begins when the patent is issued.
I seriously doubt that "retuning" constitutes novelty, and the "obvious to someone educated in the art" rejection criteria is almost impossible to refute when the examiner is obstinate.
In the field of automotive engineering the ratio of patents approved compared to patents filed is minuscule. After 6 years of work I am finally going to see mine in a couple of months.
I'll believe it when I have the document in my hand.
Even after your application is accepted for issuance, there is still a 6 month probation period where new information could be cause for rejection.
The only rational reason for withholding information, would be if you have conceived further improvements that you have not protected with additional provisional filings or complete application filings.
If you have functional prototypes and your patent is pending, and you are absolutely certain the application will be approved, there is no reason to not demonstrate and sell your idea.
The patent office will publish your patent anyway, assuming it is issued. I have received a couple of pounds of mail in the last week from companies that research newly published patents and wish to represent the patent holder in sales and licensing negotiations.
You first provisional document (good for 1 year) or your completed application, receipted and invoiced, gives you pending status, but the actual document is your real intellectual property.
Basically you seem to be in a position to sell your idea, with the single caveat that if the application is rejected then you have no intellectual property rights.
Every Patent Attorney I ever talked with gave me the line that my attorney was not that good while they were far superior. Maybe your attorney should advise you on the information I have posted here or you can research it on the USPTO site.
International filings are required within 1 year of receipt of your completed application.
Even if you file internationally there are many countries that will ignore your rights to legitimate intellectual property. Other countries will drag you into infringement suits where you are a foreigner in their jurisdiction. There are also foundations with attorneys who do more research to try to have your patent rescinded based on their research and they can argue their case in court.
Edit
I made a mistake, my patent is a Utility patent as is yours.
regards
Gary
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