{A : Type u_1} →
  {B : Type u_2} →
    {G : Type u_3} →
      [inst : CommSemiring A] →
        [inst_1 : Semiring B] →
          [inst_2 : Algebra A B] →
            [inst_3 : Group G] →
              [inst_4 : MulSemiringAction G B] →
                {motive : Algebra.IsInvariant A B G → Sort u} →
                  (t : Algebra.IsInvariant A B G) →
                    ((isInvariant : ∀ (b : B), (∀ (g : G), g • b = b) → ∃ a, (algebraMap A B) a = b) → motive ⋯) →
                      motive t