Currently, the fields' hash codes are simply added: https://github.com/dotnet/corefx/blob/master/src/System.Numerics.Vectors/src/System/Numerics/Matrix4x4.cs#L2209-L2212, https://github.com/dotnet/corefx/blob/master/src/System.Numerics.Vectors/src/System/Numerics/Matrix3x2.cs#L805-L807. It seems like it would be better to change this to use HashHelpers.Combine().