diff --git a/gtsam/linear/Makefile.am b/gtsam/linear/Makefile.am
index c29e03403..c141080ac 100644
--- a/gtsam/linear/Makefile.am
+++ b/gtsam/linear/Makefile.am
@@ -11,7 +11,7 @@ sources =
 check_PROGRAMS = 
 
 # Noise Model
-headers += SharedGaussian.h SharedDiagonal.h 
+headers += SharedGaussian.h SharedDiagonal.h  SharedNoiseModel.h
 sources += NoiseModel.cpp Errors.cpp Sampler.cpp
 check_PROGRAMS += tests/testNoiseModel tests/testErrors tests/testSampler