"Participating galleries" refers to art galleries or exhibition spaces that are involved in a specific event, program, or initiative. These galleries are actively taking part and contributing to the event or program in some way. Full definition
Check out a full list of participating galleries here. (observer.com)
You can download a map of participating galleries here. (hyperallergic.com)
Material is operated by incredible people and has a special energy that facilitates a great exchange between the different participating galleries and artist. (humorandtheabject.com)