Open Source Hardware (Case studies)

[Dakota Hamill]

Has anyone come across any case studies of businesses that have adhered to the open source model and shared all the nitty gritty details of creating, manufacturing, pricing, and selling an open source product for a profit? 

I came across an interesting talk a while back 

Open Hardware Dr. Pearce

Which was then followed by someone who wrote a book on the topic 

Open Hardware Basics and Business Alicia Gibb

https://www.amazon.com/Building-Open-Source-Hardware-Manufacturing/dp/0321906047

I know Adafruit and Sparkfun have done pretty well, but it seems like open source fits well with electrical engineering.  Arduino is now closed source?  MakerBot was a big one in the early days to go closed once they took money. 

This open source bioreactor is cool and is the type of product I'd be interested in seeing a case study on.  https://pioreactor.com

More interested in the science-hardware side of things but wondering of any other examples I've not been able to find.  Seems like there's a lot of individual projects but very few "DIYBio" style companies at the size/scale of AdaFruit or Sparkfun. 

I get that transistors are much cheaper and easier to store than enzymes.