diff --git a/CMakeLists.txt b/CMakeLists.txt
index 19ee2a8..d864845 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -85,7 +85,7 @@
 include(CMakeDependentOption)
 include(PrettyPrintCMakeList)
 
-option(SUITESPARSE "Enable SuiteSparse." ON)
+option(SUITESPARSE "Enable SuiteSparse." OFF)
 if (APPLE)
   option(ACCELERATESPARSE
     "Enable use of sparse solvers in Apple's Accelerate framework." ON)
@@ -407,16 +407,15 @@
 set(RELATIVE_CMAKECONFIG_INSTALL_DIR ${CMAKE_INSTALL_LIBDIR}/cmake/Ceres)
 
 if (SUITESPARSE)
-  # By default, if SuiteSparse and all dependencies are found, Ceres is
-  # built with SuiteSparse support.
+  # SuiteSparse support is opt-in and was explicitly requested. If it and
+  # all of its dependencies are found, Ceres is built with SuiteSparse
+  # support.
 
   # Check for SuiteSparse and dependencies.
   find_package(SuiteSparse 4.5.6 COMPONENTS CHOLMOD SPQR
     OPTIONAL_COMPONENTS Partition)
   if (SuiteSparse_FOUND)
     set(SuiteSparse_DEPENDENCY "find_dependency(SuiteSparse ${SuiteSparse_VERSION})")
-    # By default, if all of SuiteSparse's dependencies are found, Ceres is
-    # built with SuiteSparse support.
     message("-- Found SuiteSparse ${SuiteSparse_VERSION}, "
             "building with SuiteSparse.")
 
diff --git a/docs/source/installation.rst b/docs/source/installation.rst
index 2329b0f..6548281 100644
--- a/docs/source/installation.rst
+++ b/docs/source/installation.rst
@@ -629,15 +629,19 @@
    note that if ``LAPACK=ON`` and ``SUITESPARSE=ON``, the ``LAPACK`` and
    ``BLAS`` libraries used by SuiteSparse and Ceres should be the same.
 
-#. ``SUITESPARSE [Default: ON]``: By default, Ceres will link to
-   ``SuiteSparse`` if it and all of its dependencies are present. Turn
-   this ``OFF`` to build Ceres without ``SuiteSparse``.
+#. ``SUITESPARSE [Default: OFF]``: SuiteSparse support is opt-in. Turn this
+   ``ON`` to link Ceres against ``SuiteSparse``, provided it and all of its
+   dependencies are present.
 
-   .. NOTE::
+   .. WARNING::
 
-      SuiteSparse is licensed under a mixture of GPL/LGPL/Commercial
-      terms.  Ceres requires some components that are only licensed under
-      GPL/Commercial terms.
+      SuiteSparse is licensed under a mixture of GPL/LGPL/Commercial terms.
+      Ceres requires the CHOLMOD supernodal factorization and SPQR components,
+      which are only available under GPL/Commercial terms. Consequently, unless
+      you hold a commercial SuiteSparse license, a Ceres build with
+      ``SUITESPARSE=ON`` is GPL licensed. This is why SuiteSparse support is
+      opt-in rather than enabled by default. Obtaining a commercial SuiteSparse
+      license removes this restriction.
 
 #. ``ACCELERATESPARSE [Default: ON]``: By default, Ceres will link to
    Apple's Accelerate framework directly if a version of it is detected
diff --git a/docs/source/version_history.rst b/docs/source/version_history.rst
index f6a9193..a4581eb 100644
--- a/docs/source/version_history.rst
+++ b/docs/source/version_history.rst
@@ -20,6 +20,14 @@
 #. Clarify building Ceres Solver from Git sources in the installation
    documentation.
 
+Backward Incompatible API Changes
+---------------------------------
+
+#. The ``SUITESPARSE`` CMake option now defaults to ``OFF``. Passing
+   ``-DSUITESPARSE=ON`` restores the previous behavior, but makes the
+   resulting Ceres build GPL licensed unless you hold a commercial
+   SuiteSparse license.
+
 2.2.0
 =====