Is it possible for patents to have trade secrets?

Question

Is it possible to omit miscellanous or detailed mechanisms which directly depend on the main mechanism of an invention from a patent. e.g. say A is the main mechanism for an invention, B mechanism makes A extremely efficient but is dependent on A(useless without A), Is it possible to withold B as a trade secret(knowing that A would still work) and still get a valid patent. A possible reason for wanting to do this is so that non commercial or secret infringements aren't possible without additional knowledge provided by the patent holder via agreements or settlements.

I ask because most patents I have gone through seem not truthful to some point, omissive or even complex to interpret. I am aware the criteria for a successful publication is a full disclosure that can be validated by an expert in the field, I ask also because of non corporate entities e.g. the military infringing on a patent without the awareness of the inventor and the general public(say the invention is deemed weaponizable) since from the patent they can reproduce the mechanism for non commercial purposes in a classified manner.

Answer 1

In the U.S. you need to include the "best mode" embodiment of your invention. You might be able to narrowly claim A such that a disclosure sufficient to enable A, alone, does not need to mention B as part of a best mode for A. If you had not yet developed B you could patent A and then develop a trade-secret B that made A more efficient. Since you already have developed B you may need to disclose it as part of the best mode requirement.

You might note that the AIA law took some of the teeth out of the best mode requirement. No longer can your patent be torn up for lack of best mode, but ethically, a registered practitioner should not assist you in filing an application missing its best mode.

Separately, patents are often hard to read and complex. The requirement, in the U.S. is not that they could be "validated by an expert in the field" but that someone of ordinary skill in the field could implement the invention without undue experimentation.

EDIT

You can't hold back information (that you know at the time of filing) needed to make the invention in order to handicap an infringer. It would be hiding the ball. That is the essence of the reason patents are given. You tell the public all about it and then the government give you a way to protect its use for a limited time.

An invention you can claim in a way that the claimed elements tend to be externally visible would be easier to enforce.

Answer 2

Based on feedback, i'm editing my answer.

You are obligated to disclose your invention's best embodiment in the patent application. Thus if A isn't really sufficient without B I'm guessing you absolutely need to disclose both in your patent application. If however A is quite a reasonable invention by itself, and B is an independent invention (even if it relies on A). You might be able to split them into separate patents. You really should discuss this with a patent attorney as it depends on the specifics of your invention.

It is generally a good idea to obtain the broadest possible patent coverage. This comes from having the fewest possible elements in the claims. Even if you file one patent which includes both A and B, try to have some claims only on A to get the broadest patent coverage. The issue with leaving B out of the patent entirely is then it is then not protected by patent. If someone can reverse engineer it, they can implement B. Typically trade secrets are associated with internal processes like the formula for Coke or a manufacturing technique. A search algorithm might be held trade secret since it resides on company servers and would be difficult to reverse engineer. If B is a mechanism and is sold as a device, it would be open to reverse engineering and would be difficult to protect as trade secret.

I'm not sure I fully comprehend the concern with the military secretly sealing your technology. I think they are far more likely to want to buy it from you than spend the time and effort to manufacture it for themselves. But then again, I'm not a conspiracy theorist. Be advised, I am not a lawyer and this answer is not legal advice.

Answer 3

It is possible to file a patent application AND retain the ability to treat it as a trade secret. When you file, you need to file a non-publication request. There are downsides in terms of foreign patent filings in doing so, but it also means that the patent application is never published, and remains secret, until the patent actually issues. Patents take years to issue, so by the time you get a notice of allowance, you can evaluate the market and decide whether to retain it as a trade secret or go ahead and allow the patent to publish. Once it is published, of course, it is a matter of public record.

Another variation is to keep a portion of a product or service as a trade secret. For example, you may have invented a way of changing the operation of an MRI machine to generate information that can be processed in a novel manner to return a higher resolution image. You could file for a patent on the physical changes to the MRI machine without filing for a patent on your data processing method (which, in the US, would be expensive to get and at constant risk of invalidation since it involves software and algorithms). You could then have anybody who uses your patented MRI machine send the data to your facility where you process it according to your trade secret method and return the results. The trick to such a hybrid patent/trade secret combination is that there are really two freestanding inventions that happen to work together. That way while you are required to disclose the best mode for building the machine, you're not required to disclose the best mode for data processing. You'd need some strong legal advice, though, because it is threading the needle to pull it off.