diff --git a/main/src/main/scala/sbt/internal/GlobLister.scala b/main/src/main/scala/sbt/internal/GlobLister.scala
index 050d3affb..20970778a 100644
--- a/main/src/main/scala/sbt/internal/GlobLister.scala
+++ b/main/src/main/scala/sbt/internal/GlobLister.scala
@@ -74,8 +74,8 @@ private[internal] object GlobListers {
   private def covers(left: Glob, right: Glob): Boolean = {
     right.base.startsWith(left.base) && {
       left.depth == Int.MaxValue || {
-        val depth = left.base.relativize(right.base).getNameCount
-        depth < left.depth - right.depth
+        val depth = left.base.relativize(right.base).getNameCount - 1
+        depth <= left.depth - right.depth
       }
     }
   }
diff --git a/sbt/src/sbt-test/tests/glob-dsl/build.sbt b/sbt/src/sbt-test/tests/glob-dsl/build.sbt
index c6452cd51..b2f8c1c76 100644
--- a/sbt/src/sbt-test/tests/glob-dsl/build.sbt
+++ b/sbt/src/sbt-test/tests/glob-dsl/build.sbt
@@ -52,3 +52,20 @@ checkSet := {
   val expected = Seq("Bar.md", "Foo.txt").map(baseDirectory.value / "base/subdir/nested-subdir" / _)
   assert(deduped.sorted == expected)
 }
+
+val depth = taskKey[Seq[File]]("Specify redundant sources with limited depth")
+val checkDepth = taskKey[Unit]("Check that the Bar.md file is retrieved")
+
+depth / fileInputs ++= Seq(
+  sbt.io.Glob(baseDirectory.value / "base", -DirectoryFilter, 2),
+  sbt.io.Glob(baseDirectory.value / "base" / "subdir", -DirectoryFilter, 1)
+)
+
+checkDepth := {
+  val redundant = (depth / fileInputs).value.all.map(_._1.toFile)
+  assert(redundant.size == 2)
+
+  val deduped = (depth / fileInputs).value.toSet[Glob].all.map(_._1.toFile)
+  val expected = Seq("Bar.md", "Foo.txt").map(baseDirectory.value / "base/subdir/nested-subdir" / _)
+  assert(deduped.sorted == expected)
+}
diff --git a/sbt/src/sbt-test/tests/glob-dsl/test b/sbt/src/sbt-test/tests/glob-dsl/test
index 29af3c03d..2a197fb99 100644
--- a/sbt/src/sbt-test/tests/glob-dsl/test
+++ b/sbt/src/sbt-test/tests/glob-dsl/test
@@ -4,4 +4,6 @@
 
 > checkAll
 
-> checkSet
\ No newline at end of file
+> checkSet
+
+> checkDepth
\ No newline at end of file