It has been 19 years since MAME took the emulation world by storm, changing forever the way we run classic titles and protect them against the passage of time. One of MAME's great goals was to complete its transition to a free and open source license, and after ten months of work, its developers have achieved it. This opens the doors to a new dynamic, new developments, and why not, new products.
In general, emulators are a very tempting target for copyright hawks, since there are always suspicions about reverse engineering and other tricks intended to reproduce the original operation of a platform. However, the MAME emulator has never been challenged in a court during the last 19 years. Owning an emulator itself is legal, and the true conflict arises with access to ROM images. The owner of a cartridge or the main board of an arcade machine shouldn't have problems, but we know how things are on the Web, and if you want a specific ROM, it will only take you a couple of minutes to get it. MAME's leaders have stayed away from all that movement, and their intention to achieve greater transparency has never been lost sight of.
A Landmark Announcement
Finally, the official page announced last Friday that MAME is now 100% free and open source. This transition demanded ten months of work due to the large number of contributors (internal and external) who participated in the project. After studying all the available licensing options, it was concluded that the vast majority of files (over 90 percent) would be under the BSD 3-Clause license, while the entire project will be distributed under GNU GPL 2.0+. The only thing that still retains a proprietary profile is the term "MAME" and its logo.
The official MAME page also published a logical notice indicating that all derived projects will need to receive the appropriate permissions from their contributors, and code that was distributed under MAME's previous license cannot be included or linked to MAME without the corresponding license changes. This implies that initiatives like MAMEUI and MESSUI will need to make several adjustments, though I imagine it will be a matter of time and goodwill.
