Voivod
Voivod, the Canadian heavy metal band, was influenced by Gentle Giant. Here is an excerpt from an interview with Voivod's drummer, Michel "Away" Langevin, from Brave Words & Bloody Knuckles magazine, issue #93, page 42-43.
"Even though we live in Montreal, we're originally from Jonquiere in northern Quebec. Jonquiere is an industrial town, and that's why there was a real machine-like feel to the early records. Piggy [former guitarist Denis D'Amour] tried to replicate the machinery kind of sound we heard in Jonquiere, and he tried to combine that with progressive rock. Voivod was always really inspired by Gentle Giant, King Crimson and a lot of obscure kraut rock. When we'd do interviews in the US, we'd mention all these obscure German prog bands and they'd wonder what we were talking about (laughs). Prog rock contributed immensely to our sound, and prog is bigger in Quebec than anywhere else in North America."