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Limited run PCBs - where's copyright???

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From time to time I've seen limited run PCBs made on this site and others. typically stuff like shunt regs, constant current sinks, anode loads etc. Could somebody explain:

a) What actual legallly enforceable copyright issues there are - can you copyright something like a CCS made of obvious parts?

b) What's 'good practice' - when should the originator of a circuit be reasonably expected to take a royalty, and when is a circuit such common knowledge that a royalty would be unreasonable?

c) In what ways do the originators of circuits 'take a cut' of sales - in royalties, in free boards from the guy that makes the boards up, any other methods?

I'm unclear as to all this and would very much like to know the answers to the above. Andy
 
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Basically you can copyright any original work whether or not it is based on common practice. The topology itself may be common practice, but the analysis, testing, and prototyping that results in the final design can be copyrighted. Such things would include choices of active devices, associated component values, and the way in which they are combined.

Whether any, most, or all designs should be copyrighted is debatable.
(Mine are all copyrighted)

Basically such designs can be:

a.)Stolen, unfortunately often the case on the internet where IP is not always respected. Anything made and distributed to others without the designer's express permission would fall into this category.

b.)Made freely available for non commercial use by the designer. I think most board group buys could qualify for this provided that the person arranging the group buy was not doing it for profit.

c.) An exclusive or none exclusive license can be granted to specific entities or individuals to commercialize a design, with a small monetary royalty being paid for each unit built and sold.

d.) Other forms of compensation such as work in kind, parts, or as you noted a couple of sets of boards.

The key thing is to ask permission first.. I am always flattered when someone thinks enough of one of my designs to want to copy it and distribute it. I almost always say yes even if there is no expectation of anything in return.

I have made agreements based on b, c, and d, and been a victim of a.

Both my Dynaco MKIII and ST-70 driver boards have been cloned by others without my permission. In a couple of cases the work is clearly derivative, and in at least one case it was an exact copy of my board right down to the brands of the parts used. In this case, the MKIII driver board they admitted to copying my design in the literature, but as I never published that design it was obviously a case of very thorough reverse engineering. I was provided with samples by a friendly 3rd party who non-the-less would not disclose where he got them from. And I was never approached for permission either.

Lest anyone think this is a good way to make a living, it hasn't proven to be the case so far. :D Now I have a real job. ;)
 
European and american legislation and th the practice thereof is somewhat different when it comes to patent and copyright.

I don't think you can get copyright on a known circuit just by changing the component values and/or makes, if the topology is already known. You can in fact copyright the drawing itself, but not the topology
You can also coyright a PCB layout of a known topology. As far as using other ppl's copyrighted material, anyone is free to do so for personal use , - i.e. non-commercial. I think this is universally true, even if there has been cases of legal actions on a mostly "let's-scare the-****-out-of-them" basis. Any patent or copyright can be exploited for personal use.

If you think you have an idea " for money's worth", going at it for real, you are in for a very complicated legal job - world wide patents are an extremely expensive task.
 
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True you can't copyright topologies that are in the public domain, but watch what happens when you verbatim copy someone elses design down to the type and brand of output devices as well as aspects of the physical design that are clearly identifiable. ;) Legal departments at large companies spend a lot of time litigating over these sorts of issues, even in the case where patent infringement is not involved.

Given that there are many ways to skin a cat I would be surprised if you choose exactly the same tube types and ended up with identical component values across the board. No two designers are going to approach a problem from exactly the same angle, and end up at exactly the same result, similar does not count, however when everything ends up being exactly the same - that is an indication of plagiarism, just what copyright law is intended to prevent.

Some designs are distributed with the intent that they be copied or used as the basis for product design. These are usually termed reference designs and the respective manufacturers indicate that these may be used without consideration to royalties, etc. Companies like Mullard, RCA, and GE did this all the time just look at the back of their old tube manuals. Many semiconductor manufacturers carry on this practice till this day, see National, Analog Devices and others for examples.

Many of my tube designs used small amounts of local current feedback nearly 20 yrs ago, and I was very jealous of that secret as it was not commonly known or employed at the time - it came straight from my experience with semiconductors and works reasonably well. I no longer use it though, as i now use more linear tubes.
 
You cannot copyright a circuit. You cannot copyright a design (though in narrow cases, you can get a design patent). If you reverse engineer a Krell and clone it right down to the type numbers, that's perfectly OK legally as long as the copyrightable parts (i.e., PCB artwork) aren't directly copied.

If you Xerox a commercial board, etch some up, and sell them, you've got legal liability. If you re-lay out the board yourself, you're in the clear. If a circuit is patented, you're running a MUCH higher legal risk.

I'm only talking legality here, not morality, which seems to be alarmingly plastic.

Usual disclaimer- I'm not an attorney. There's very good reading on these issues at Nolo Press's website.
 
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