diff --git a/src/libxrpl/tx/Transactor.cpp b/src/libxrpl/tx/Transactor.cpp
index 2745079f6e..c387c3a586 100644
--- a/src/libxrpl/tx/Transactor.cpp
+++ b/src/libxrpl/tx/Transactor.cpp
@@ -160,16 +160,28 @@ Transactor::preflight1(PreflightContext const& ctx, std::uint32_t flagMask)
         return temINVALID_FLAG;
     }
 
-    if (!hasSponsor && hasSponsorFlags)
+    if (!hasSponsor)
     {
-        JLOG(ctx.j.debug()) << "preflight1: sponsor flags without sponsor definition";
-        return temINVALID_FLAG;
-    }
+        if (hasSponsorFlags)
+        {
+            JLOG(ctx.j.debug()) << "preflight1: sponsor flags without sponsor definition";
+            return temINVALID_FLAG;
+        }
 
-    if (!hasSponsor && hasSponsorSig)
+        if (hasSponsorSig)
+        {
+            JLOG(ctx.j.debug()) << "preflight1: sponsor signature without sponsor definition";
+            return temMALFORMED;
+        }
+    }
+    else if (hasSponsorFlags)
     {
-        JLOG(ctx.j.debug()) << "preflight1: sponsor signature without sponsor definition";
-        return temMALFORMED;
+        auto const sponsorFlags = ctx.tx.getFieldU32(sfSponsorFlags);
+        if ((sponsorFlags & ~(spfSponsorFee | spfSponsorReserve)) || sponsorFlags == 0)
+        {
+            JLOG(ctx.j.debug()) << "preflight1: invalid sponsor flags";
+            return temINVALID_FLAG;
+        }
     }
 
     if (auto const ret = preflight0(ctx, flagMask))
@@ -218,6 +230,13 @@ Transactor::preflight1(PreflightContext const& ctx, std::uint32_t flagMask)
         return temMALFORMED;
     }
 
+    // if (hasSponsor && hasSponsorFlags &&
+    //     ctx.tx.getFieldU32(sfSponsorFlags) == 0)
+    // {
+    //     JLOG(ctx.j.debug()) << "preflight1: sponsor with no sponsorship flags";
+    //     return temINVALID_FLAG;
+    // }
+
     return tesSUCCESS;
 }
 
diff --git a/src/test/app/Sponsor_test.cpp b/src/test/app/Sponsor_test.cpp
index e3e230479f..9f56a5c8a5 100644
--- a/src/test/app/Sponsor_test.cpp
+++ b/src/test/app/Sponsor_test.cpp
@@ -360,7 +360,7 @@ public:
         env.close();
 
         // Invalid Sponsor Account (Account = Sponsor.Account)
-        env(noop(alice), sponsor::as(alice), ter(temMALFORMED));
+        env(noop(alice), sponsor::as(alice, spfSponsorFee), ter(temMALFORMED));
 
         // Invalid Sponsor Account
         // (SponsorSignature is specified but Sponsor.Account is not specified)
@@ -378,6 +378,9 @@ public:
             sponsor::as(sponsor, (spfSponsorFee | spfSponsorReserve) + 1),
             ter(temINVALID_FLAG));
 
+        // SponsorFlags=0 with valid sponsor (no sponsorship purpose)
+        env(noop(alice), sponsor::as(sponsor, 0), ter(temINVALID_FLAG));
+
         // Invalid Flags without sponsor
         auto tx = noop(alice);
         tx[sfSponsorFlags.jsonName] = spfSponsorFee | spfSponsorReserve;