diff --git a/shardy/dialect/sdy/transforms/propagation/sharding_projection.h b/shardy/dialect/sdy/transforms/propagation/sharding_projection.h
index bac0091b..17748b17 100644
--- a/shardy/dialect/sdy/transforms/propagation/sharding_projection.h
+++ b/shardy/dialect/sdy/transforms/propagation/sharding_projection.h
@@ -49,6 +49,10 @@ struct FactorSharding {
            isMinorMost == other.isMinorMost &&
            overflowAxes == other.overflowAxes;
   }
+
+  bool operator!=(const FactorSharding& other) const {
+    return !(*this == other);
+  }
 };
 
 using FactorIndexToSharding = llvm::DenseMap<int64_t, FactorSharding>;
@@ -65,6 +69,10 @@ struct TensorFactorShardings {
            replicatedAxes == other.replicatedAxes;
   }
 
+  bool operator!=(const TensorFactorShardings& other) const {
+    return !(*this == other);
+  }
+
   // Updates the sharding axes of the given `factorIndex` to `newAxes` if
   // 1. this tensor is associated with that factor, and
   // 2. `newAxes` strictly contains existing axes. For example, ["a", "b"]
@@ -177,6 +185,10 @@ class ShardingProjection {
     return operands == other.operands && results == other.results;
   }
 
+  bool operator!=(const ShardingProjection& other) const {
+    return !(*this == other);
+  }
+
  private:
   SmallVector<TensorFactorShardings> operands;
   SmallVector<TensorFactorShardings> results;