MIDI Manufacturers Association

The MIDI Manufacturers Association (MMA) is an organization where companies work together to create the standards that assure compatibility among MIDI products.[1] The MMA is a U.S. organization established in 1985 by the original developers of the MIDI 1.0 Specification in 1983.[2] Since 1985 the MMA has produced 11 new specifications and adopted 38 sets of enhancements to MIDI.

(source: https://en.wikipedia.org/wiki/MIDI_Manufacturers_Association)