It is my opinion that "lawyers" are keen to remind us that if someone makes no attempt at protecting their intellectual property they have actually forfeited some rights to claim how it gets used.
Must be why big software companies hide their source code behind firewalls and lawyers and guys with guns on their hip.
Nice that pwillard attributed Kadlec even though you had to gut and rework so much. Concur its best to take the high road. Also concur in principle with full "credit headings" but am still wrestling with details.
If a company develops something original then quits or otherwise sells that line of source code to a buyer or bankruptcy receiver, then the purchaser might not be obligated to credit the developer, as the developer (or his employer) got cash or whatever.
Is such a commercial developer or its employee prohibited from using ideas seen on this forum? There is some good stuff here. Or is it okay as long as "credit headings" from open source and forum posts are included in the commercial source code?
Or is it completely prohibited that an employee to use open source while "on the clock"? After reading forums for a few days I've become so "infected by good ideas" you could almost say I am now entirely unfit for commercial employment as an engineer!
Well, some already say that, but for different reasons...
Some have even claimed that its not legally possible for an employee to use Arduino at work. The idea being that its impossible to simultaneously protect the intellectual property of ones employer while also protecting the common property of the open source community. I certainly hope they are mistaken!
When a Delta Airlines seat-back panel reboots it briefly shows a picture of "Tux" and then credits open source Linux followed by developers copyright notice of proprietary software followed by a list of commercial packages that were also used. I bet some time, money and lawyers got poured into those details. Thats waay above my pay grade; I'm just trying to "do right" on a simple one-off project for work, have separately contacted a team member about it.
Most folks here are hobbyists, and a few open source developers like the Arduino team and Ladyada that dont "owe their souls to the company store". Thats the kinda stuff we all love and I am eagerly jumping in too.
It's wonderful to create purely personal works that can be returned in their entirety as open source, but we still have to decide how much "credit headings" to use. For the core platform, one could simply credit the Arduino team only, but as retrolefty pointed out the Arduino team themselves stood on other shoulders, should my sketch "credit headings" include those too?
The Arduino written stuff
The AVR gcc compiler/linker stuff
The wiring projects stuff
The processing projects stuff
If so, as the open source world goes on, headings of each new work would include a growing tree of its entire "genealogy" so to speak, My sketch "credit headings" for Arduino also need to include all the underpinnings of Arduino like those enumerated by retrolefty. Digging up the source code for those reveals more ancient ancestors. And so on, "all the way back to Alan Turing". That could get cumbersome.
On the other hand is so much simpler to just "credit headings" to the Arduino project, and leave it at that. The "genealogy" can be traced further back by looking up the Arduino project online. This works pretty well for a thriving, well organized, and long lived project like Arduino. But traceback can easily fail for folks who contribute then move on to other things without a lifetime email address, URL or such. And it will eventually fail in every case, for no human work is eternal, especially on the internet. Could we assume by the time such traceback fails those sources are too old to be relevant?
So even "credit headings" for a purely CC work are not cut-and-dry simple.
As a new Arduino zealot, its an honor to discuss philosophy with the gods. Your views and advice are valued, thanks! And these questions have practical implications too. In any case Arduino has greatly expanded the horizons of open source. May Arduino live long and prosper.