I have an idea for an invention that requires 2 pieces. Each one of those 2 pieces has no useful purpose on its own.

Is it possible to patent each one of those 2 pieces separately as independent inventions?

The argument is that they will be useful when combined with X, Y, Z, etc.


2 Answers 2


You can possibly patent X as being useful to combine with Y and visa versa. The "useful" criteria is a very low bar as long as you are not talking about something that might be seen as abstract. The person I learned from to pass the patent bar said of a hypothetical chemical "pour it on the grass - if it kills it, that's useful; if it causes faster growth, that's also useful.

Lets say X is a novel handle and Y is something that would be easier to use if it had a handle. They are both useful. See this patent for a handle. Its claim 1 is:

Device handle (1) with two handle supports (2) that can be attached to a device, between the ends of which are remote from the device, a handle bar (3) is attached, characterized in that the longitudinal axis (a) of the handle bar (3) is opposite the connecting line (b) between the two ends (attachment points) of the handle supports (2) intended for attachment to the device are laterally offset.

You might say its structure has no use but one of its attributes is "can be attached to a device". I would re-think the idea that something worth patenting has no use.

Also US569019, a retractable handle for a suitcase. This fancy handle sitting on a shelf is useless. A suitcase with no handle is not too useful.

  • I'm not sure the quote ""poor it on the grass - if it kills it, that's useful; if it kills it that's also useful." is quite right. Seems to be redundant.
    – Eric S
    Commented Apr 6, 2022 at 14:25
  • Thanks - fixed it.
    – George White
    Commented Apr 6, 2022 at 15:16

It is a fundamental requirement (at least in the US) that a patented process or device be useful. So if the part truly has “no useful purpose” than the answer is the part is unpatentable by itself.

That said, the threshold for usefulness is quite low. I'd say that a part that is useful in combination with a second part is probably useful enough. For instance a chemical which has no use by itself may be useful if it enhances another chemical or reaction.

  • thanks. can you give a detail answer for this? patents.stackexchange.com/questions/24608/… Commented Apr 5, 2022 at 17:50
  • As I commented on that question, it is unanswerable without more info.
    – Eric S
    Commented Apr 5, 2022 at 17:52
  • The useful is a very low bar.
    – George White
    Commented Apr 5, 2022 at 21:51
  • @GeorgeWhite True, but the OP specifically used the term “no useful purpose”.
    – Eric S
    Commented Apr 6, 2022 at 1:25
  • Your answer is correct and I just upvoted it. But If they can be combined to make something useful I think he misunderstands the meaning of useless. See the handle examples in a related question.
    – George White
    Commented Apr 6, 2022 at 1:29

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .