diff --git a/matching.go b/matching.go
index e32ff6e..56c6135 100644
--- a/matching.go
+++ b/matching.go
@@ -6,11 +6,11 @@ type matchIndex struct {
 	endIdx   int
 }
 
-// Returns true if the given matchIndex is an improper subset of any of the indices in the slice.
+// Returns true if the given matchIndex has ovelrap with any of the indices in the slice.
 // When we add an index to our slice, we want to make sure a larger match isn't already present.
 func overlaps(idx matchIndex, idxes []matchIndex) bool {
 	for _, val := range idxes {
-		if idx.startIdx >= val.startIdx && idx.endIdx <= val.endIdx {
+		if (idx.startIdx > val.startIdx && idx.startIdx < val.endIdx) || (idx.endIdx > val.startIdx && idx.endIdx < val.endIdx) {
 			// A zero-length match doesn't overlap if it is located at the start or end
 			// of the other match
 			if !(idx.startIdx == idx.endIdx && (idx.startIdx == val.startIdx || idx.startIdx == val.endIdx)) {