diff --git a/testdata/drc/drcSimpleTests_50.drc b/testdata/drc/drcSimpleTests_50.drc
new file mode 100644
index 000000000..c4fe22019
--- /dev/null
+++ b/testdata/drc/drcSimpleTests_50.drc
@@ -0,0 +1,14 @@
+
+source $drc_test_source
+target $drc_test_target
+
+# Problem of #826 was deep-mode universal DRC with threading
+
+deep
+threads(4)
+
+l7 = input(7, 0)
+l7.output(7, 0)
+
+l7.drc((angle == 0) & (length < 12.0)).extended_out(1.dbu).output(100, 0)
+
diff --git a/testdata/drc/drcSimpleTests_50.gds b/testdata/drc/drcSimpleTests_50.gds
new file mode 100644
index 000000000..667f1e7be
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diff --git a/testdata/drc/drcSimpleTests_au50.gds b/testdata/drc/drcSimpleTests_au50.gds
new file mode 100644
index 000000000..55e3f8ecf
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