diff --git a/c3.js b/c3.js
index d060110..231d7ce 100644
--- a/c3.js
+++ b/c3.js
@@ -875,6 +875,8 @@
         function showTooltip(selectedData, mouse) {
             var tWidth, tHeight;
             var svgLeft, tooltipLeft, tooltipRight, tooltipTop, chartRight;
+            // don't show tooltip when no data
+            if (selectedData.filter(function (d) { return d.value; }).length === 0) { return; }
             // Construct tooltip
             tooltip.html(__tooltip_contents(selectedData))
                 .style("visibility", "hidden")
diff --git a/c3.min.js b/c3.min.js
index 57cedc0..7401f5f 100644
--- a/c3.min.js
+++ b/c3.min.js
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