diff --git a/Ix.NET/Source/System.Interactive.Async.Providers.Tests/System.Interactive.Async.Providers.Tests.csproj b/Ix.NET/Source/System.Interactive.Async.Providers.Tests/System.Interactive.Async.Providers.Tests.csproj
index 63d772cb85..f2e562ca3c 100644
--- a/Ix.NET/Source/System.Interactive.Async.Providers.Tests/System.Interactive.Async.Providers.Tests.csproj
+++ b/Ix.NET/Source/System.Interactive.Async.Providers.Tests/System.Interactive.Async.Providers.Tests.csproj
@@ -22,7 +22,7 @@
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     <PackageReference Include="xunit" Version="2.4.1" />
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diff --git a/Ix.NET/Source/System.Interactive.Async.Tests/System.Interactive.Async.Tests.csproj b/Ix.NET/Source/System.Interactive.Async.Tests/System.Interactive.Async.Tests.csproj
index 0bcab474c9..64e8f4db32 100644
--- a/Ix.NET/Source/System.Interactive.Async.Tests/System.Interactive.Async.Tests.csproj
+++ b/Ix.NET/Source/System.Interactive.Async.Tests/System.Interactive.Async.Tests.csproj
@@ -19,7 +19,7 @@
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-    <PackageReference Include="FluentAssertions" Version="6.2.0" />
+    <PackageReference Include="FluentAssertions" Version="6.4.0" />
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diff --git a/Ix.NET/Source/System.Interactive.Tests/System.Interactive.Tests.csproj b/Ix.NET/Source/System.Interactive.Tests/System.Interactive.Tests.csproj
index e83b53e4ba..2d8b2b9bcf 100644
--- a/Ix.NET/Source/System.Interactive.Tests/System.Interactive.Tests.csproj
+++ b/Ix.NET/Source/System.Interactive.Tests/System.Interactive.Tests.csproj
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diff --git a/Ix.NET/Source/System.Linq.Async.Queryable.Tests/System.Linq.Async.Queryable.Tests.csproj b/Ix.NET/Source/System.Linq.Async.Queryable.Tests/System.Linq.Async.Queryable.Tests.csproj
index 25381dc38a..6abdffd2c9 100644
--- a/Ix.NET/Source/System.Linq.Async.Queryable.Tests/System.Linq.Async.Queryable.Tests.csproj
+++ b/Ix.NET/Source/System.Linq.Async.Queryable.Tests/System.Linq.Async.Queryable.Tests.csproj
@@ -19,7 +19,7 @@
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diff --git a/Ix.NET/Source/System.Linq.Async.Tests/System.Linq.Async.Tests.csproj b/Ix.NET/Source/System.Linq.Async.Tests/System.Linq.Async.Tests.csproj
index 68f67daebc..ec7e2d5e46 100644
--- a/Ix.NET/Source/System.Linq.Async.Tests/System.Linq.Async.Tests.csproj
+++ b/Ix.NET/Source/System.Linq.Async.Tests/System.Linq.Async.Tests.csproj
@@ -41,7 +41,7 @@
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+    <PackageReference Include="FluentAssertions" Version="6.4.0" />
     <PackageReference Include="xunit" Version="2.4.1" />
   </ItemGroup>