diff --git a/include/xrpl/protocol/ExportLimits.h b/include/xrpl/protocol/ExportLimits.h
index a8d2fa79a..05b2046b6 100644
--- a/include/xrpl/protocol/ExportLimits.h
+++ b/include/xrpl/protocol/ExportLimits.h
@@ -29,6 +29,18 @@ struct ExportLimits
     // reserves a separate operator signer must select fewer validators.
     static constexpr std::size_t maxCommitteeMembers = 32;
 
+    // V1 witnesses require the standard 80% quorum of the intent-selected
+    // committee, rounded up. The intent selects members but cannot lower this
+    // threshold. Split quotient/remainder arithmetic avoids overflow while
+    // preserving ceil(memberCount * 0.8).
+    static constexpr std::size_t
+    committeeQuorumThreshold(std::size_t memberCount)
+    {
+        auto const quotient = memberCount / 5;
+        auto const remainder = memberCount % 5;
+        return quotient * 4 + (remainder * 4 + 4) / 5;
+    }
+
     // Maximum exports a single hook execution may produce. Hook API ABI
     // constant hook_api::max_export must stay equal.
     static constexpr std::uint8_t maxExportsPerHook = 2;
diff --git a/src/test/protocol/ExportKeylet_test.cpp b/src/test/protocol/ExportKeylet_test.cpp
index 6cc040daf..0b754c0a5 100644
--- a/src/test/protocol/ExportKeylet_test.cpp
+++ b/src/test/protocol/ExportKeylet_test.cpp
@@ -27,6 +27,7 @@
 #include <xrpl/protocol/ValidatorBitset.h>
 #include <xrpl/protocol/digest.h>
 
+#include <array>
 #include <cstring>
 
 namespace ripple {
@@ -116,6 +117,15 @@ public:
         BEAST_EXPECT(ExportLimits::maxCommitteeMaskBytes == 32);
         BEAST_EXPECT(
             ExportLimits::maxCommitteeMembers == STTx::maxMultiSigners());
+
+        std::array<std::size_t, 11> constexpr expected{
+            0, 1, 2, 3, 4, 4, 5, 6, 7, 8, 8};
+        for (std::size_t members = 0; members < expected.size(); ++members)
+            BEAST_EXPECT(
+                ExportLimits::committeeQuorumThreshold(members) ==
+                expected[members]);
+        BEAST_EXPECT(ExportLimits::committeeQuorumThreshold(28) == 23);
+        BEAST_EXPECT(ExportLimits::committeeQuorumThreshold(32) == 26);
     }
 
     void