Despite all the fun debating the meaning of "open source", it's still a legitimate headline because it describes the article's position clearly. From the articl

Despite all the fun debating the meaning of "open source", it's still a legitimate headline because it describes the article's position clearly. From the article: > MAME's source code has long been freely available, but it's never technically been open source. Instead it's been available under a modified BSID license that prohibits, among other things, commercial use of the code.