diff --git a/README.md b/README.md
index 2f6a171..1367780 100644
--- a/README.md
+++ b/README.md
@@ -27,7 +27,7 @@ This repository provides `case_validate` as an adaptation of the `pyshacl` comma
 To see a human-readable validation report of an instance-data file:
 
 ```bash
-case_validate input.json
+case_validate input.json [input-2.json ...]
 ```
 
 If `input.json` is not conformant, a report will be emitted, and `case_validate` will exit with status `1`.  (This is a `pyshacl` behavior, where `0` and `1` report validation success.  Status of >`1` is for other errors.)
diff --git a/case_utils/case_validate/__init__.py b/case_utils/case_validate/__init__.py
index 30a1124..97f7e66 100644
--- a/case_utils/case_validate/__init__.py
+++ b/case_utils/case_validate/__init__.py
@@ -56,7 +56,7 @@ def main() -> None:
     # parser.
     logging.basicConfig(level=logging.DEBUG if ("--debug" in sys.argv or "-d" in sys.argv) else logging.INFO)
 
-    case_version_choices_list = ["none", "case-" + CURRENT_CASE_VERSION]
+    built_version_choices_list = ["none", "case-" + CURRENT_CASE_VERSION]
 
     # Add arguments specific to case_validate.
     parser.add_argument(
@@ -67,7 +67,7 @@ def main() -> None:
     )
     parser.add_argument(
       "--built-version",
-      choices=tuple(case_version_choices_list),
+      choices=tuple(built_version_choices_list),
       default="case-"+CURRENT_CASE_VERSION,
       help="Monolithic aggregation of CASE ontology files at certain versions.  Does not require networking to use.  Default is most recent CASE release."
     )
@@ -119,12 +119,14 @@ def main() -> None:
       default=sys.stdout,
     )
 
-    parser.add_argument("in_graph")
+    parser.add_argument("in_graph", nargs="+")
 
     args = parser.parse_args()
 
     data_graph = rdflib.Graph()
-    data_graph.parse(args.in_graph)
+    for in_graph in args.in_graph:
+        _logger.debug("in_graph = %r.", in_graph)
+        data_graph.parse(in_graph)
 
     ontology_graph = rdflib.Graph()
     if args.built_version != "none":
diff --git a/tests/case_utils/case_validate/cli/Makefile b/tests/case_utils/case_validate/cli/Makefile
index ac10b28..f61d421 100644
--- a/tests/case_utils/case_validate/cli/Makefile
+++ b/tests/case_utils/case_validate/cli/Makefile
@@ -39,7 +39,9 @@ files_to_generate := \
   format_unspecified_output_jsonld.jsonld \
   format_unspecified_output_turtle.ttl \
   format_unspecified_output_txt.txt \
-  format_unspecified_output_unspecified.txt
+  format_unspecified_output_unspecified.txt \
+  split_data_graph_PASS.txt \
+  split_data_graph_XFAIL.txt
 
 all: \
   $(files_to_generate)
@@ -183,3 +185,34 @@ format_unspecified_output_unspecified.txt: \
 	    $< \
 	    > _$@
 	mv _$@ $@
+
+split_data_graph_PASS.txt: \
+  $(tests_srcdir)/.venv.done.log \
+  $(top_srcdir)/.ontology.done.log \
+  $(top_srcdir)/case_utils/case_validate/__init__.py \
+  $(top_srcdir)/case_utils/ontology/__init__.py \
+  split_data_graph_1.json \
+  split_data_graph_2.json
+	rm -f _$@
+	source $(tests_srcdir)/venv/bin/activate \
+	  && case_validate \
+	    --debug \
+	    split_data_graph_1.json \
+	    split_data_graph_2.json \
+	    > _$@
+	mv _$@ $@
+
+split_data_graph_XFAIL.txt: \
+  $(tests_srcdir)/.venv.done.log \
+  $(top_srcdir)/.ontology.done.log \
+  $(top_srcdir)/case_utils/case_validate/__init__.py \
+  $(top_srcdir)/case_utils/ontology/__init__.py \
+  split_data_graph_1.json
+	rm -f _$@
+	source $(tests_srcdir)/venv/bin/activate \
+	  && case_validate \
+	    --debug \
+	    split_data_graph_1.json \
+	    > _$@ \
+	    ; rc=$$? ; test 1 -eq $$rc
+	mv _$@ $@
diff --git a/tests/case_utils/case_validate/cli/split_data_graph_1.json b/tests/case_utils/case_validate/cli/split_data_graph_1.json
new file mode 100644
index 0000000..04237ba
--- /dev/null
+++ b/tests/case_utils/case_validate/cli/split_data_graph_1.json
@@ -0,0 +1,16 @@
+{
+    "@context": {
+        "kb": "http://example.org/kb/",
+        "case-investigation": "https://ontology.caseontology.org/case/investigation/",
+        "uco-core": "https://unifiedcyberontology.org/ontology/uco/core#"
+    },
+    "@graph": [
+        {
+            "@id": "kb:provenance-record-1",
+            "@type": "case-investigation:ProvenanceRecord",
+            "uco-core:object": {
+                "@id": "kb:file-1"
+            }
+        }
+    ]
+}
diff --git a/tests/case_utils/case_validate/cli/split_data_graph_2.json b/tests/case_utils/case_validate/cli/split_data_graph_2.json
new file mode 100644
index 0000000..54df483
--- /dev/null
+++ b/tests/case_utils/case_validate/cli/split_data_graph_2.json
@@ -0,0 +1,13 @@
+{
+    "@context": {
+        "kb": "http://example.org/kb/",
+        "uco-observable": "https://unifiedcyberontology.org/ontology/uco/observable#"
+    },
+    "@graph": [
+        {
+            "@id": "kb:file-1",
+            "@type": "uco-observable:File"
+        }
+    ]
+}
+
diff --git a/tests/case_utils/case_validate/cli/split_data_graph_PASS.txt b/tests/case_utils/case_validate/cli/split_data_graph_PASS.txt
new file mode 100644
index 0000000..0c16da6
--- /dev/null
+++ b/tests/case_utils/case_validate/cli/split_data_graph_PASS.txt
@@ -0,0 +1,2 @@
+Validation Report
+Conforms: True
diff --git a/tests/case_utils/case_validate/cli/split_data_graph_XFAIL.txt b/tests/case_utils/case_validate/cli/split_data_graph_XFAIL.txt
new file mode 100644
index 0000000..f5fa2c7
--- /dev/null
+++ b/tests/case_utils/case_validate/cli/split_data_graph_XFAIL.txt
@@ -0,0 +1,10 @@
+Validation Report
+Conforms: False
+Results (1):
+Constraint Violation in ClassConstraintComponent (http://www.w3.org/ns/shacl#ClassConstraintComponent):
+	Severity: sh:Violation
+	Source Shape: [ sh:class core:UcoObject ; sh:minCount Literal("1", datatype=xsd:integer) ; sh:nodeKind sh:BlankNodeOrIRI ; sh:path core:object ]
+	Focus Node: kb:provenance-record-1
+	Value Node: kb:file-1
+	Result Path: core:object
+	Message: Value does not have class core:UcoObject