diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..21fc4d1
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+/PATSTAT/EU_CH_scope/cpc_defs.csv
diff --git a/TODO.ipynb b/TODO.ipynb
index 0a52f13..d251021 100644
--- a/TODO.ipynb
+++ b/TODO.ipynb
@@ -9,6 +9,28 @@
     "collapsed": false
    }
   },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "outputs": [],
+   "source": [
+    "# Patent classes"
+   ],
+   "metadata": {
+    "collapsed": false
+   }
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "outputs": [],
+   "source": [
+    "# AI keywords PATSTAT and WOS"
+   ],
+   "metadata": {
+    "collapsed": false
+   }
+  },
   {
    "cell_type": "code",
    "execution_count": null,