diff --git a/README.md b/README.md
index bd13047f4..4b05524a2 100644
--- a/README.md
+++ b/README.md
@@ -231,7 +231,7 @@ Clad also provides certain flags to save and print the generated derivative code
 - To print the Clad generated derivative: `-Xclang -plugin-arg-clad -Xclang -fdump-derived-fn`
 
 ## How to install
-At the moment, LLVM/Clang 5.0.x - 17.0.x are supported.
+At the moment, LLVM/Clang 7.0.x - 17.0.x are supported.
 
 ### Conda Installation
 
diff --git a/include/clad/Differentiator/Compatibility.h b/include/clad/Differentiator/Compatibility.h
index 0ac2dcbdc..62d71641c 100644
--- a/include/clad/Differentiator/Compatibility.h
+++ b/include/clad/Differentiator/Compatibility.h
@@ -21,33 +21,17 @@ namespace clad_compat {
 using namespace clang;
 using namespace llvm;
 
-// Compatibility helper function for creation CompoundStmt. Clang 6 and above use Create.
-// Clang 15
+// Compatibility helper function for creation CompoundStmt.
 // Clang 15 and above use a extra param FPFeatures in CompoundStmt::Create.
 
 static inline bool SourceManager_isPointWithin(const SourceManager& SM,
                                                SourceLocation Loc,
                                                SourceLocation B,
                                                SourceLocation E) {
-#if CLANG_VERSION_MAJOR == 5
-  return Loc == B || Loc == E || (SM.isBeforeInTranslationUnit(B, Loc) &&
-                                  SM.isBeforeInTranslationUnit(Loc, E));
-#elif CLANG_VERSION_MAJOR >= 6
   return SM.isPointWithin(Loc, B, E);
-#endif
 }
 
-#if CLANG_VERSION_MAJOR == 5
-#define CLAD_COMPAT_CLANG15_CompoundStmt_Create_ExtraParam(Node) /**/
-#define CLAD_COMPAT_CLANG15_CompoundStmt_Create_ExtraParam1(CS) /**/
-#define CLAD_COMPAT_CLANG15_CompoundStmt_Create_ExtraParam2(FP) /**/
-static inline CompoundStmt* CompoundStmt_Create(
-        const ASTContext &Ctx, ArrayRef<Stmt *> Stmts,
-        SourceLocation LB, SourceLocation RB)
-{
-   return new (Ctx) CompoundStmt(Ctx, Stmts, LB, RB);
-}
-#elif CLANG_VERSION_MAJOR < 15
+#if CLANG_VERSION_MAJOR < 15
 #define CLAD_COMPAT_CLANG15_CompoundStmt_Create_ExtraParam(Node) /**/
 #define CLAD_COMPAT_CLANG15_CompoundStmt_Create_ExtraParam1(CS) /**/
 #define CLAD_COMPAT_CLANG15_CompoundStmt_Create_ExtraParam2(FP) /**/
@@ -87,31 +71,10 @@ NamespaceDecl_Create(ASTContext& C, DeclContext* DC, bool Inline,
 }
 #endif
 
-// Clang 6 rename Sema::ForRedeclaration to Sema::ForVisibleRedeclaration
-
-#if CLANG_VERSION_MAJOR == 5
-   const auto Sema_ForVisibleRedeclaration = Sema::ForRedeclaration;
-#elif CLANG_VERSION_MAJOR >= 6
-   const auto Sema_ForVisibleRedeclaration = Sema::ForVisibleRedeclaration;
-#endif
-
-
-// Clang 6 rename Declarator to DeclaratorContext, but Declarator is used
-// as name for another class.
-
-#if CLANG_VERSION_MAJOR == 5
-   using DeclaratorContext = Declarator;
-#elif CLANG_VERSION_MAJOR >= 6
-   using DeclaratorContext = DeclaratorContext;
-#endif
-
-
 // Clang 7 add one extra param in UnaryOperator constructor.
 
-#if CLANG_VERSION_MAJOR < 7
-   #define CLAD_COMPAT_CLANG7_UnaryOperator_ExtraParams /**/
-#elif CLANG_VERSION_MAJOR >= 7
-   #define CLAD_COMPAT_CLANG7_UnaryOperator_ExtraParams ,Node->canOverflow()
+#if CLANG_VERSION_MAJOR >= 7
+#define CLAD_COMPAT_CLANG7_UnaryOperator_ExtraParams , Node->canOverflow()
 #endif
 
 
diff --git a/lib/Differentiator/CladUtils.cpp b/lib/Differentiator/CladUtils.cpp
index 164f5ddda..16da9e5cf 100644
--- a/lib/Differentiator/CladUtils.cpp
+++ b/lib/Differentiator/CladUtils.cpp
@@ -243,7 +243,7 @@ namespace clad {
       // Find the builtin derivatives/numerical diff namespace
       DeclarationName Name = &C.Idents.get(namespc);
       LookupResult R(S, Name, SourceLocation(), Sema::LookupNamespaceName,
-                     clad_compat::Sema_ForVisibleRedeclaration);
+                     Sema::ForVisibleRedeclaration);
       S.LookupQualifiedName(R, DC,
                             /*allowBuiltinCreation*/ false);
       if (!shouldExist && R.empty())
diff --git a/lib/Differentiator/VisitorBase.cpp b/lib/Differentiator/VisitorBase.cpp
index 5b0cf2507..fc0857fb8 100644
--- a/lib/Differentiator/VisitorBase.cpp
+++ b/lib/Differentiator/VisitorBase.cpp
@@ -168,11 +168,8 @@ namespace clad {
     NamespaceDecl* PrevNS = nullptr;
     // From Sema::ActOnStartNamespaceDef:
     if (II) {
-      LookupResult R(m_Sema,
-                     II,
-                     noLoc,
-                     Sema::LookupOrdinaryName,
-                     clad_compat::Sema_ForVisibleRedeclaration);
+      LookupResult R(m_Sema, II, noLoc, Sema::LookupOrdinaryName,
+                     Sema::ForVisibleRedeclaration);
       m_Sema.LookupQualifiedName(R, m_Sema.CurContext->getRedeclContext());
       NamedDecl* FoundDecl =
           R.isSingleResult() ? R.getRepresentativeDecl() : nullptr;
@@ -423,11 +420,8 @@ namespace clad {
     if (Result)
       return Result;
     DeclarationName CladName = &m_Context.Idents.get("clad");
-    LookupResult CladR(m_Sema,
-                       CladName,
-                       noLoc,
-                       Sema::LookupNamespaceName,
-                       clad_compat::Sema_ForVisibleRedeclaration);
+    LookupResult CladR(m_Sema, CladName, noLoc, Sema::LookupNamespaceName,
+                       Sema::ForVisibleRedeclaration);
     m_Sema.LookupQualifiedName(CladR, m_Context.getTranslationUnitDecl());
     assert(!CladR.empty() && "cannot find clad namespace");
     Result = cast<NamespaceDecl>(CladR.getFoundDecl());
@@ -440,11 +434,8 @@ namespace clad {
     CXXScopeSpec CSS;
     CSS.Extend(m_Context, CladNS, noLoc, noLoc);
     DeclarationName TapeName = &m_Context.Idents.get(ClassName);
-    LookupResult TapeR(m_Sema,
-                       TapeName,
-                       noLoc,
-                       Sema::LookupUsingDeclName,
-                       clad_compat::Sema_ForVisibleRedeclaration);
+    LookupResult TapeR(m_Sema, TapeName, noLoc, Sema::LookupUsingDeclName,
+                       Sema::ForVisibleRedeclaration);
     m_Sema.LookupQualifiedName(TapeR, CladNS, CSS);
     assert(!TapeR.empty() && isa<TemplateDecl>(TapeR.getFoundDecl()) &&
            "cannot find clad::tape");
diff --git a/tools/ClangPlugin.cpp b/tools/ClangPlugin.cpp
index 70e39aa1b..c4ab7039a 100644
--- a/tools/ClangPlugin.cpp
+++ b/tools/ClangPlugin.cpp
@@ -330,7 +330,7 @@ namespace clad {
       DeclarationName Name = &C.Idents.get("clad");
       Sema &SemaR = m_CI.getSema();
       LookupResult R(SemaR, Name, SourceLocation(), Sema::LookupNamespaceName,
-                     clad_compat::Sema_ForVisibleRedeclaration);
+                     Sema::ForVisibleRedeclaration);
       SemaR.LookupQualifiedName(R, C.getTranslationUnitDecl(),
                                 /*allowBuiltinCreation*/ false);
       m_HasRuntime = !R.empty();