diff --git a/Mathlib/Data/DFinsupp/Basic.lean b/Mathlib/Data/DFinsupp/Basic.lean
index 41d436996172bb..384702ae090d26 100644
--- a/Mathlib/Data/DFinsupp/Basic.lean
+++ b/Mathlib/Data/DFinsupp/Basic.lean
@@ -1710,6 +1710,13 @@ def prod [∀ i, Zero (β i)] [∀ (i) (x : β i), Decidable (x ≠ 0)] [CommMon
 #align dfinsupp.prod DFinsupp.prod
 #align dfinsupp.sum DFinsupp.sum
 
+@[to_additive (attr := simp)]
+theorem _root_.map_dfinsupp_prod
+    {R S H : Type*} [∀ i, Zero (β i)] [∀ (i) (x : β i), Decidable (x ≠ 0)]
+    [CommMonoid R] [CommMonoid S] [MonoidHomClass H R S] (h : H) (f : Π₀ i, β i)
+    (g : ∀ i, β i → R) : h (f.prod g) = f.prod fun a b => h (g a b) :=
+  map_prod _ _ _
+
 @[to_additive]
 theorem prod_mapRange_index {β₁ : ι → Type v₁} {β₂ : ι → Type v₂} [∀ i, Zero (β₁ i)]
     [∀ i, Zero (β₂ i)] [∀ (i) (x : β₁ i), Decidable (x ≠ 0)] [∀ (i) (x : β₂ i), Decidable (x ≠ 0)]
@@ -2248,12 +2255,8 @@ variable {R S : Type*}
 
 variable [∀ i, Zero (β i)] [∀ (i) (x : β i), Decidable (x ≠ 0)]
 
-@[to_additive (attr := simp)]
-theorem map_dfinsupp_prod [CommMonoid R] [CommMonoid S] (h : R →* S) (f : Π₀ i, β i)
-    (g : ∀ i, β i → R) : h (f.prod g) = f.prod fun a b => h (g a b) :=
-  h.map_prod _ _
-#align monoid_hom.map_dfinsupp_prod MonoidHom.map_dfinsupp_prod
-#align add_monoid_hom.map_dfinsupp_sum AddMonoidHom.map_dfinsupp_sum
+#noalign monoid_hom.map_dfinsupp_prod
+#noalign add_monoid_hom.map_dfinsupp_sum
 
 @[to_additive]
 theorem coe_dfinsupp_prod [Monoid R] [CommMonoid S] (f : Π₀ i, β i) (g : ∀ i, β i → R →* S) :
@@ -2271,40 +2274,10 @@ theorem dfinsupp_prod_apply [Monoid R] [CommMonoid S] (f : Π₀ i, β i) (g : 
 
 end MonoidHom
 
-namespace RingHom
-
-variable {R S : Type*}
-
-variable [∀ i, Zero (β i)] [∀ (i) (x : β i), Decidable (x ≠ 0)]
-
-@[simp]
-theorem map_dfinsupp_prod [CommSemiring R] [CommSemiring S] (h : R →+* S) (f : Π₀ i, β i)
-    (g : ∀ i, β i → R) : h (f.prod g) = f.prod fun a b => h (g a b) :=
-  h.map_prod _ _
-#align ring_hom.map_dfinsupp_prod RingHom.map_dfinsupp_prod
-
-@[simp]
-theorem map_dfinsupp_sum [NonAssocSemiring R] [NonAssocSemiring S] (h : R →+* S) (f : Π₀ i, β i)
-    (g : ∀ i, β i → R) : h (f.sum g) = f.sum fun a b => h (g a b) :=
-  h.map_sum _ _
-#align ring_hom.map_dfinsupp_sum RingHom.map_dfinsupp_sum
-
-end RingHom
-
-namespace MulEquiv
-
-variable {R S : Type*}
-
-variable [∀ i, Zero (β i)] [∀ (i) (x : β i), Decidable (x ≠ 0)]
-
-@[to_additive (attr := simp)]
-theorem map_dfinsupp_prod [CommMonoid R] [CommMonoid S] (h : R ≃* S) (f : Π₀ i, β i)
-    (g : ∀ i, β i → R) : h (f.prod g) = f.prod fun a b => h (g a b) :=
-  h.map_prod _ _
-#align mul_equiv.map_dfinsupp_prod MulEquiv.map_dfinsupp_prod
-#align add_equiv.map_dfinsupp_sum AddEquiv.map_dfinsupp_sum
-
-end MulEquiv
+#noalign ring_hom.map_dfinsupp_prod
+#noalign ring_hom.map_dfinsupp_sum
+#noalign mul_equiv.map_dfinsupp_prod
+#noalign add_equiv.map_dfinsupp_sum
 
 /-! The above lemmas, repeated for `DFinsupp.sumAddHom`. -/
 
diff --git a/Mathlib/LinearAlgebra/Basic.lean b/Mathlib/LinearAlgebra/Basic.lean
index f7369a18e059ee..a061722eccab85 100644
--- a/Mathlib/LinearAlgebra/Basic.lean
+++ b/Mathlib/LinearAlgebra/Basic.lean
@@ -1109,11 +1109,7 @@ section Sum
 
 variable [∀ i, Zero (γ i)] [∀ (i) (x : γ i), Decidable (x ≠ 0)]
 
-@[simp]
-theorem map_dfinsupp_sum (f : M →ₛₗ[σ₁₂] M₂) {t : Π₀ i, γ i} {g : ∀ i, γ i → M} :
-    f (t.sum g) = t.sum fun i d => f (g i d) :=
-  f.map_sum
-#align linear_map.map_dfinsupp_sum LinearMap.map_dfinsupp_sum
+#noalign linear_map.map_dfinsupp_sum
 
 theorem coe_dfinsupp_sum (t : Π₀ i, γ i) (g : ∀ i, γ i → M →ₛₗ[σ₁₂] M₂) :
     ⇑(t.sum g) = t.sum fun i d => g i d := rfl
@@ -1923,11 +1919,7 @@ variable [RingHomInvPair τ₁₂ τ₂₁] [RingHomInvPair τ₂₁ τ₁₂]
 variable {γ : ι → Type*} [DecidableEq ι]
 
 
-@[simp]
-theorem map_dfinsupp_sum [∀ i, Zero (γ i)] [∀ (i) (x : γ i), Decidable (x ≠ 0)] (f : M ≃ₛₗ[τ₁₂] M₂)
-    (t : Π₀ i, γ i) (g : ∀ i, γ i → M) : f (t.sum g) = t.sum fun i d => f (g i d) :=
-  f.map_sum _
-#align linear_equiv.map_dfinsupp_sum LinearEquiv.map_dfinsupp_sum
+#noalign linear_equiv.map_dfinsupp_sum
 
 @[simp]
 theorem map_dfinsupp_sumAddHom [∀ i, AddZeroClass (γ i)] (f : M ≃ₛₗ[τ₁₂] M₂) (t : Π₀ i, γ i)
diff --git a/Mathlib/LinearAlgebra/Eigenspace/Basic.lean b/Mathlib/LinearAlgebra/Eigenspace/Basic.lean
index ac57b8661000f2..26fa7e38914549 100644
--- a/Mathlib/LinearAlgebra/Eigenspace/Basic.lean
+++ b/Mathlib/LinearAlgebra/Eigenspace/Basic.lean
@@ -199,7 +199,7 @@ theorem eigenspaces_independent (f : End K V) : CompleteLattice.Independent f.ei
           id.def, sub_smul, Submodule.subtype_apply, Submodule.coe_sub, Submodule.coe_smul_of_tower,
           LinearMap.sub_apply, mem_eigenspace_iff.1 v.prop, algebraMap_end_apply]
       · rw [DFinsupp.sum_mapRange_index.linearMap]
-      · simp only [DFinsupp.sumAddHom_apply, LinearMap.id_coe, LinearMap.map_dfinsupp_sum, id.def,
+      · simp only [DFinsupp.sumAddHom_apply, LinearMap.id_coe, map_dfinsupp_sum, id.def,
           LinearMap.toAddMonoidHom_coe, DFinsupp.lsum_apply_apply]
       · simp only [DFinsupp.sum_mapRange_index.linearMap, LinearMap.id_comp]
     -- Therefore, by the induction hypothesis, all entries of `l'` are zero.