I've always been fond of referring to such a thing as "source available" - and commercial software such as Radiator where you only get an un-obfuscated version of the source with a purchase as "source supplied".

"Available" just seems like a better word than "open" for this sort of case.

(the author apologises for overuse of quotes in the above but preferred to be consistent even at the potential cost of some irritation and/or incorrect usage)