Preliminary Patent Applications are only good for 1 year, and that is a very very firm deadline at USPTO. You can’t go an hour over a year. Firm deadline. Specified in law.
However you can add new inventive material to material that is expiring in an existing preliminary patent application and then file the whole sum of all those ideas as a new preliminary patent application. The old ideas may or may not be includable in any utility or design patent that may eventually be filed. Your preliminary patent application is not published by USPTO, and is secret unless you publish it, or disclose it to a blabblemouth, and all humans are blabbermouths, so if you disclose it to anybody, and for sure any corporation, it is now “publicly known” and not “innovative”.
But the new material, could go into claims for subsequently filed utility patents, and hence the new material could be of value to a big corporation, that buys the said core technology patent specified above, which you can read at patents.google.com or at least just the cover sheet that contains the drawing and the Abstract, about a 56 second read, not quite a whole minute. It could be worth your time.
The nature of inventing already includes a lot of tweeking, and improving, this or that part of the invention. and it’s not a penalty or detriment to me to do a few tweeks a year for my preliminary patent applications, so they can be re-filed as improved versions of their former selves. Only the new tweeks are subsequently claimable, but nobody wants a second best version of an invention, and whoever buys my positions may want to add tweeks of their own, perhaps in consultation with me, or just purely on their own. One can claim around the old material so as to avoid an objection based on lack of novelty. Preliminary patent applications do not need to contain any claims at all — just a detailed description of what you think you invented that is adequate allow a person skilled in the art to build it, make it, or use it.
Since the preliminary patent applications portfolio is just a gratuity that I will toss in to sweeten the deal on my main patent and it’s assignment, there’s no issue of non-disclosure agreements. If I have a real buyer who buys my main patent, they do not need to see the patent applications portfolio before they pay for the main patent. Once their check clears, they can have the follow-on patents, and me with them, if they want. This means they have paid me $8 million by 1 April 2019, or not less than $16 million at some time thereafter.
Inventors want their stuff to be made and used. I won’t be coy about that. Yes, I do. All my stuff. And I would like to participate, on a consulting basis, as an inventor/adviser helping the buyer get the maximum return on the money they have paid me, which is more money than I could expect to use in the balance of my expected lifetime.
A lot of my ideas appear at robertfentongary.com and I tell you my WordPress pals some of them, and some appear on Facebook under my pages there. I am interested in getting value metals off the seafloor. I am interested in secure military communications equipment. I am seeking a hack-proof way to send signals through fiber optic cable. Only about a billion people had their information spilled in the past three years, but in 2019, it could be nine times that many, so every single living human might become interested in prevent further harm to themselves by compromise of their private data. Out of that group, one human might emerge and say “Yeh, we need this patent, this is an un-hackable technology, and it is a valuable one.”
It will be a very smart person in California or Boston, with a lot of money, and vision, most likely not connected with Bitcoin or any crypto-currency. Also, most likely not a criminal. And it is highly likely to be a person or corporation holding at least a Top Secret Codeword security clearance. This could be a venture capital firm, or it could be one of the genius people at Lockheed Martin, or Apple, or Google, or Microsoft, or Amazon.