You've designed a great widget or board, and it's time to get some backers to turn it into a shipping product. Up goes a page on Kickstarter, and the questions and money start rolling in.

At some point, you might be asked whether your thing is going to be open source. Or, your intention is to make it open source when it ships. Great, there's a lot of community interest in open source hardware and your Kickstarter goes well.

Only you can't actually open source it, because it has a binary blob to support a chip. Or an NDA for the datasheets. Or you thought a published API was all you had to do. In some cases, you can't because you didn't understand what open source meant, and what people expected is far from what you've offered.

Hardware projects on Kickstarter are great, but I see too many with intentions or vague statements about open source that are straying close to misleading. Some variation from the promises made is to be expected, but making a major claim about a product (like saying it is or will be open source) is quite different.

You probably aren't actually trying to fleece people. But as someone who actually makes Open Source Hardware, I feel like you might be treading into the area without playing fair. So before you trumpet that your widget is open source, here's some things to think about.

Do you understand what Open Source means?

A very important first step is to make sure you are using the same meanings as everyone else. Have you read the OSHW definition, and definitions of various licenses for your firmware? Do you understand the implications of linking a binary blob into an otherwise open source piece of code? Some licenses may not allow you to do this (so-called "linking clause").

Are you prepared to release all your design files in their original source form? It's not sufficient to release compiled or generated files (eg, PCB gerbers), you need to provide the source used to create and edit the design.

Do your due-diligence before mentioning open source

This is a really basic thing, you should already have a good understanding about the parts you are using and what restrictions are in place for those parts. For example, if you need to sign an NDA to get the datasheet, there is a low chance you could reasonably meet Open Source.

Are the parts well documented enough to be easily replaced by alternatives? Do you need special toolchains or libraries with licenses that are incompatible with open source?

Have you chosen a license?

It can be hard to judge if you have given much thought to what open source means if you haven't selected a license already.  You will need to consider a license for both the hardware design and the firmware or software involved in it.

License terms could exclude it from being considered as open source. For example, if you do not allow derivative works this does not meet the OSHW definition.

Conclusion

I really want to see more OSHW designs, and sites like Kickstarter are really good at getting them started. But don't just hop on the open source bandwagon without thinking about it carefully. That just makes it harder for those of us following the rules to appear honest, and you'll have disappointed customers too.