This FAQ and others are available on the OSHWA FAQ page: http://www.oshwa.org/faq/
What’s a USB vendor ID (VID) and product ID (PID) and what should I do about them?
USB vendor IDs (VID) and product IDs (PID) are 16-bit numbers used to identify USB devices to a computer or other host. Each vendor ID is assigned by the USB Implementers Forum to a specific company, which in turn assign a PID to individual products. The VID and PID are then embedded in the product and communicated to the computer when the device is plugged in, along with text strings describing the vendor and product and additional descriptors about the communication protocols supported by the device.
Because a USB VID is specific to a particular organization, derivatives shouldn’t use the VID and PID of the original hardware. This can be problematic for small open-source hardware projects because it costs $5000 to get your own vendor ID (and more for permission to use the USB logo). Because this can be a lot of money for a small project, people have taken various approaches to avoiding the need to purchase a vendor ID. If you’re using an off-the-shelf chip for USB communication, you may be able to use the VID/PID of that chip (e.g. with FTDI chips). OpenMoko has opened up their VID for use by free and open-source software and hardware communities. In some cases, a device may work correctly regardless of the VID/PID it uses, since its actual capabilities are specified by other descriptors. In general, though, the current USB VID and PID scheme doesn’t work particularly well with open-source hardware and its encouragement of derivative works. (For example, here’s one attempt to get a VID for open-source projects.) Ian Lesnet gave a talk on the USB VID/PID situation(slides) at the 2012 Open Hardware Summit.
OSHWA is interested in improving this situation by educating the USB IF about the needs of the open-source hardware community and to explain the USB VID/PID situation to the open-source hardware community. If you’re interested in helping out with this effort, please get in touch.
This FAQ and others are available on the OSHWA FAQ page: http://www.oshwa.org/faq/