diff --git a/cache/tracking/src/main/scala/sbt/Tracked.scala b/cache/tracking/src/main/scala/sbt/Tracked.scala
index 66b15546f..e17c4052c 100644
--- a/cache/tracking/src/main/scala/sbt/Tracked.scala
+++ b/cache/tracking/src/main/scala/sbt/Tracked.scala
@@ -232,23 +232,23 @@ object FileFunction {
   type UpdateFunction = (ChangeReport[File], ChangeReport[File]) => Set[File]
 
   /**
-    Generic change-detection helper used to help build / artifact generation /
-    etc. steps detect whether or not they need to run. Returns a function whose
-    input is a Set of input files, and subsequently executes the action function
-    (which does the actual work: compiles, generates resources, etc.), returning
-    a Set of output files that it generated.
-
-    The input file and resulting output file state is cached in
-    cacheBaseDirectory. On each invocation, the state of the input and output
-    files from the previous run is compared against the cache, as is the set of
-    input files. If a change in file state / input files set is detected, the
-    action function is re-executed.
-
-    @param cacheBaseDirectory The folder in which to store
-    @param inStyle The strategy by which to detect state change in the input files from the previous run
-    @param outStyle The strategy by which to detect state change in the output files from the previous run
-    @param action The work function, which receives a list of input files and returns a list of output files
-    */
+   * Generic change-detection helper used to help build / artifact generation /
+   * etc. steps detect whether or not they need to run. Returns a function whose
+   * input is a Set of input files, and subsequently executes the action function
+   * (which does the actual work: compiles, generates resources, etc.), returning
+   * a Set of output files that it generated.
+   *
+   * The input file and resulting output file state is cached in
+   * cacheBaseDirectory. On each invocation, the state of the input and output
+   * files from the previous run is compared against the cache, as is the set of
+   * input files. If a change in file state / input files set is detected, the
+   * action function is re-executed.
+   *
+   * @param cacheBaseDirectory The folder in which to store
+   * @param inStyle The strategy by which to detect state change in the input files from the previous run
+   * @param outStyle The strategy by which to detect state change in the output files from the previous run
+   * @param action The work function, which receives a list of input files and returns a list of output files
+   */
   def cached(cacheBaseDirectory: File, inStyle: FilesInfo.Style = FilesInfo.lastModified, outStyle: FilesInfo.Style = FilesInfo.exists)(action: Set[File] => Set[File]): Set[File] => Set[File] =
     cached(cacheBaseDirectory)(inStyle, outStyle)((in, out) => action(in.checked))
 
diff --git a/compile/inc/src/main/scala/sbt/inc/Compile.scala b/compile/inc/src/main/scala/sbt/inc/Compile.scala
index a5da65860..40a11e286 100644
--- a/compile/inc/src/main/scala/sbt/inc/Compile.scala
+++ b/compile/inc/src/main/scala/sbt/inc/Compile.scala
@@ -206,6 +206,7 @@ private final class AnalysisCallback(internalMap: File => Option[File], external
   def usedName(sourceFile: File, name: String) = add(usedNames, sourceFile, name)
 
   def nameHashing: Boolean = options.nameHashing
+  def includeSynthToNameHashing: Boolean = options.includeSynthToNameHashing
 
   def get: Analysis = addUsedNames(addCompilation(addProductsAndDeps(Analysis.empty(nameHashing = nameHashing))))
 
diff --git a/compile/inc/src/main/scala/sbt/inc/IncOptions.scala b/compile/inc/src/main/scala/sbt/inc/IncOptions.scala
index b38fed952..17b65d65f 100644
--- a/compile/inc/src/main/scala/sbt/inc/IncOptions.scala
+++ b/compile/inc/src/main/scala/sbt/inc/IncOptions.scala
@@ -80,7 +80,11 @@ final class IncOptions(
      * Once Scala compiler sources are refactored to work well with name hashing algorithm this option will be
      * deleted immediately.
      */
-    val antStyle: Boolean) extends Product with Serializable {
+    val antStyle: Boolean,
+    /**
+     * Include synthetic methods into the dependency tracking by name hashing.
+     */
+    val includeSynthToNameHashing: Boolean) extends Product with Serializable {
 
   /**
    * Secondary constructor introduced to make IncOptions to be binary compatible with version that didn't have
@@ -90,59 +94,72 @@ final class IncOptions(
     apiDiffContextSize: Int, apiDumpDirectory: Option[java.io.File], newClassfileManager: () => ClassfileManager) = {
     this(transitiveStep, recompileAllFraction, relationsDebug, apiDebug, apiDiffContextSize,
       apiDumpDirectory, newClassfileManager, IncOptions.recompileOnMacroDefDefault, IncOptions.nameHashingDefault,
-      IncOptions.antStyleDefault)
+      IncOptions.antStyleDefault, IncOptions.includeSynthToNameHashingDefault)
+  }
+
+  def this(transitiveStep: Int, recompileAllFraction: Double, relationsDebug: Boolean, apiDebug: Boolean,
+    apiDiffContextSize: Int, apiDumpDirectory: Option[java.io.File], newClassfileManager: () => ClassfileManager,
+    recompileOnMacroDef: Boolean, nameHashing: Boolean, antStyle: Boolean) = {
+    this(transitiveStep, recompileAllFraction, relationsDebug, apiDebug,
+      apiDiffContextSize, apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing,
+      antStyle, IncOptions.includeSynthToNameHashingDefault)
   }
 
   assert(!(antStyle && nameHashing), "Name hashing and Ant-style cannot be enabled at the same time.")
 
   def withTransitiveStep(transitiveStep: Int): IncOptions = {
     new IncOptions(transitiveStep, recompileAllFraction, relationsDebug, apiDebug, apiDiffContextSize,
-      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle)
+      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle, includeSynthToNameHashing)
   }
 
   def withRecompileAllFraction(recompileAllFraction: Double): IncOptions = {
     new IncOptions(transitiveStep, recompileAllFraction, relationsDebug, apiDebug, apiDiffContextSize,
-      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle)
+      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle, includeSynthToNameHashing)
   }
 
   def withRelationsDebug(relationsDebug: Boolean): IncOptions = {
     new IncOptions(transitiveStep, recompileAllFraction, relationsDebug, apiDebug, apiDiffContextSize,
-      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle)
+      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle, includeSynthToNameHashing)
   }
 
   def withApiDebug(apiDebug: Boolean): IncOptions = {
     new IncOptions(transitiveStep, recompileAllFraction, relationsDebug, apiDebug, apiDiffContextSize,
-      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle)
+      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle, includeSynthToNameHashing)
   }
 
   def withApiDiffContextSize(apiDiffContextSize: Int): IncOptions = {
     new IncOptions(transitiveStep, recompileAllFraction, relationsDebug, apiDebug, apiDiffContextSize,
-      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle)
+      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle, includeSynthToNameHashing)
   }
 
   def withApiDumpDirectory(apiDumpDirectory: Option[File]): IncOptions = {
     new IncOptions(transitiveStep, recompileAllFraction, relationsDebug, apiDebug, apiDiffContextSize,
-      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle)
+      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle, includeSynthToNameHashing)
   }
 
   def withNewClassfileManager(newClassfileManager: () => ClassfileManager): IncOptions = {
     new IncOptions(transitiveStep, recompileAllFraction, relationsDebug, apiDebug, apiDiffContextSize,
-      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle)
+      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle, includeSynthToNameHashing)
   }
 
   def withRecompileOnMacroDef(recompileOnMacroDef: Boolean): IncOptions = {
     new IncOptions(transitiveStep, recompileAllFraction, relationsDebug, apiDebug, apiDiffContextSize,
-      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle)
+      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle, includeSynthToNameHashing)
   }
 
   def withNameHashing(nameHashing: Boolean): IncOptions = {
     new IncOptions(transitiveStep, recompileAllFraction, relationsDebug, apiDebug, apiDiffContextSize,
-      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle)
+      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle, includeSynthToNameHashing)
+  }
+
+  def withIncludeSynthToNameHashing(includeSynthToNameHashing: Boolean): IncOptions = {
+    new IncOptions(transitiveStep, recompileAllFraction, relationsDebug, apiDebug, apiDiffContextSize,
+      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle, includeSynthToNameHashing)
   }
 
   def withAntStyle(antStyle: Boolean): IncOptions = {
     new IncOptions(transitiveStep, recompileAllFraction, relationsDebug, apiDebug, apiDiffContextSize,
-      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle)
+      apiDumpDirectory, newClassfileManager, recompileOnMacroDef, nameHashing, antStyle, includeSynthToNameHashing)
   }
 
   //- EXPANDED CASE CLASS METHOD BEGIN -//
@@ -219,6 +236,8 @@ object IncOptions extends Serializable {
   private val recompileOnMacroDefDefault: Boolean = true
   private[sbt] val nameHashingDefault: Boolean = true
   private val antStyleDefault: Boolean = false
+  // This should default to false
+  private[sbt] val includeSynthToNameHashingDefault = java.lang.Boolean.getBoolean("sbt.inc.include_synth")
   val Default = IncOptions(
     //    1. recompile changed sources
     // 2(3). recompile direct dependencies and transitive public inheritance dependencies of sources with API changes in 1(2).
diff --git a/compile/interface/src/main/scala/xsbt/ExtractUsedNames.scala b/compile/interface/src/main/scala/xsbt/ExtractUsedNames.scala
index 56f67f3e8..281131736 100644
--- a/compile/interface/src/main/scala/xsbt/ExtractUsedNames.scala
+++ b/compile/interface/src/main/scala/xsbt/ExtractUsedNames.scala
@@ -41,6 +41,8 @@ import scala.tools.nsc._
 class ExtractUsedNames[GlobalType <: CallbackGlobal](val global: GlobalType) extends Compat {
   import global._
 
+  @inline def debug(msg: => String) = if (settings.verbose.value) inform(msg)
+
   def extract(unit: CompilationUnit): Set[String] = {
     val tree = unit.body
     val extractedByTreeWalk = extractByTreeWalk(tree)
@@ -122,7 +124,7 @@ class ExtractUsedNames[GlobalType <: CallbackGlobal](val global: GlobalType) ext
     }
 
     (symbol != NoSymbol) &&
-      !symbol.isSynthetic &&
+      (callback.includeSynthToNameHashing || !symbol.isSynthetic) &&
       !emptyName(symbol.name)
   }
 }
diff --git a/compile/interface/src/test/scala/xsbt/ExtractAPISpecification.scala b/compile/interface/src/test/scala/xsbt/ExtractAPISpecification.scala
index 839955689..3d58699e9 100644
--- a/compile/interface/src/test/scala/xsbt/ExtractAPISpecification.scala
+++ b/compile/interface/src/test/scala/xsbt/ExtractAPISpecification.scala
@@ -15,7 +15,7 @@ class ExtractAPISpecification extends Specification {
 
   def stableExistentialNames: Boolean = {
     def compileAndGetFooMethodApi(src: String): Def = {
-      val compilerForTesting = new ScalaCompilerForUnitTesting
+      val compilerForTesting = new ScalaCompilerForUnitTesting(nameHashing = false)
       val sourceApi = compilerForTesting.extractApiFromSrc(src)
       val FooApi = sourceApi.definitions().find(_.name() == "Foo").get.asInstanceOf[ClassLike]
       val fooMethodApi = FooApi.structure().declared().find(_.name == "foo").get
@@ -66,7 +66,7 @@ class ExtractAPISpecification extends Specification {
          |  class Foo extends Namers
          |}
          |""".stripMargin
-    val compilerForTesting = new ScalaCompilerForUnitTesting
+    val compilerForTesting = new ScalaCompilerForUnitTesting(nameHashing = false)
     val apis = compilerForTesting.extractApisFromSrcs(reuseCompilerInstance = false)(List(src1, src2), List(src2))
     val _ :: src2Api1 :: src2Api2 :: Nil = apis.toList
     val namerApi1 = selectNamer(src2Api1)
@@ -92,7 +92,7 @@ class ExtractAPISpecification extends Specification {
     val srcC6 = "class C6 extends AnyRef with X { self: X with Y => }"
     val srcC7 = "class C7 { _ => }"
     val srcC8 = "class C8 { self => }"
-    val compilerForTesting = new ScalaCompilerForUnitTesting
+    val compilerForTesting = new ScalaCompilerForUnitTesting(nameHashing = false)
     val apis = compilerForTesting.extractApisFromSrcs(reuseCompilerInstance = true)(
       List(srcX, srcY, srcC1, srcC2, srcC3, srcC4, srcC5, srcC6, srcC7, srcC8)
     ).map(x => collectFirstClass(x.definitions))
diff --git a/compile/interface/src/test/scala/xsbt/ScalaCompilerForUnitTesting.scala b/compile/interface/src/test/scala/xsbt/ScalaCompilerForUnitTesting.scala
index 95a27a30d..31faf2a24 100644
--- a/compile/interface/src/test/scala/xsbt/ScalaCompilerForUnitTesting.scala
+++ b/compile/interface/src/test/scala/xsbt/ScalaCompilerForUnitTesting.scala
@@ -20,7 +20,7 @@ import ScalaCompilerForUnitTesting.ExtractedSourceDependencies
  * Provides common functionality needed for unit tests that require compiling
  * source code using Scala compiler.
  */
-class ScalaCompilerForUnitTesting(nameHashing: Boolean = false) {
+class ScalaCompilerForUnitTesting(nameHashing: Boolean, includeSynthToNameHashing: Boolean = false) {
 
   /**
    * Compiles given source code using Scala compiler and returns API representation
@@ -127,7 +127,7 @@ class ScalaCompilerForUnitTesting(nameHashing: Boolean = false) {
   private def compileSrcs(groupedSrcs: List[List[String]],
     reuseCompilerInstance: Boolean): (Seq[File], TestCallback) = {
     withTemporaryDirectory { temp =>
-      val analysisCallback = new TestCallback(nameHashing)
+      val analysisCallback = new TestCallback(nameHashing, includeSynthToNameHashing)
       val classesDir = new File(temp, "classes")
       classesDir.mkdir()
 
diff --git a/interface/src/main/java/xsbti/AnalysisCallback.java b/interface/src/main/java/xsbti/AnalysisCallback.java
index a51628f15..9a342fdf1 100644
--- a/interface/src/main/java/xsbti/AnalysisCallback.java
+++ b/interface/src/main/java/xsbti/AnalysisCallback.java
@@ -59,4 +59,8 @@ public interface AnalysisCallback
 	 *       Do not depend on it, please.
 	 */
 	boolean nameHashing();
+	/**
+	 * Include synthetic methods into the dependency tracking by name hashing.
+	 */
+	boolean includeSynthToNameHashing();
 }
\ No newline at end of file
diff --git a/interface/src/test/scala/xsbti/TestCallback.scala b/interface/src/test/scala/xsbti/TestCallback.scala
index f0658597b..04c9b5756 100644
--- a/interface/src/test/scala/xsbti/TestCallback.scala
+++ b/interface/src/test/scala/xsbti/TestCallback.scala
@@ -5,7 +5,7 @@ import scala.collection.mutable.ArrayBuffer
 import xsbti.api.SourceAPI
 import xsbti.DependencyContext._
 
-class TestCallback(override val nameHashing: Boolean = false) extends AnalysisCallback
+class TestCallback(override val nameHashing: Boolean, override val includeSynthToNameHashing: Boolean) extends AnalysisCallback
 {
 	val sourceDependencies = new ArrayBuffer[(File, File, DependencyContext)]
 	val binaryDependencies = new ArrayBuffer[(File, String, File, DependencyContext)]
diff --git a/notes/0.13.12/include_synth.markdown b/notes/0.13.12/include_synth.markdown
new file mode 100644
index 000000000..0348f2b03
--- /dev/null
+++ b/notes/0.13.12/include_synth.markdown
@@ -0,0 +1,10 @@
+  [@eed3si9n]: https://github.com/eed3si9n
+  [@jsuereth]: https://github.com/jsuereth
+  [@dwijnand]: http://github.com/dwijnand
+  [@Duhemm]: http://github.com/Duhemm
+  [@gkossakowski]: https://github.com/gkossakowski
+  [2573]: https://github.com/sbt/sbt/issues/2537
+
+### Bug fixes
+
+- Provides a workaround flag `incOptions := incOptions.value.withIncludeSynthToNameHashing(true)` for name hashing not including synthetic methods. This will not be enabled by default in sbt 0.13. It can also enabled by passing `sbt.inc.include_synth=true` to JVM. [#2537][2573] by [@eed3si9h][@eed3si9h]
diff --git a/sbt/src/sbt-test/source-dependencies/naha-synthetic/A.scala b/sbt/src/sbt-test/source-dependencies/naha-synthetic/A.scala
new file mode 100644
index 000000000..acafe2da1
--- /dev/null
+++ b/sbt/src/sbt-test/source-dependencies/naha-synthetic/A.scala
@@ -0,0 +1 @@
+case class A(a: Int)
diff --git a/sbt/src/sbt-test/source-dependencies/naha-synthetic/B.scala b/sbt/src/sbt-test/source-dependencies/naha-synthetic/B.scala
new file mode 100644
index 000000000..2c4519ab3
--- /dev/null
+++ b/sbt/src/sbt-test/source-dependencies/naha-synthetic/B.scala
@@ -0,0 +1 @@
+class B { def test(a: A) = a.copy() }
diff --git a/sbt/src/sbt-test/source-dependencies/naha-synthetic/build.sbt b/sbt/src/sbt-test/source-dependencies/naha-synthetic/build.sbt
new file mode 100644
index 000000000..cd5970b1c
--- /dev/null
+++ b/sbt/src/sbt-test/source-dependencies/naha-synthetic/build.sbt
@@ -0,0 +1,5 @@
+lazy val root = (project in file(".")).
+  settings(
+    scalaVersion := "2.11.7",
+    incOptions := incOptions.value.withIncludeSynthToNameHashing(true)
+  )
diff --git a/sbt/src/sbt-test/source-dependencies/naha-synthetic/changes/A.scala b/sbt/src/sbt-test/source-dependencies/naha-synthetic/changes/A.scala
new file mode 100644
index 000000000..57eb90cee
--- /dev/null
+++ b/sbt/src/sbt-test/source-dependencies/naha-synthetic/changes/A.scala
@@ -0,0 +1 @@
+case class A(a: Int) { private def copy = ??? }
diff --git a/sbt/src/sbt-test/source-dependencies/naha-synthetic/test b/sbt/src/sbt-test/source-dependencies/naha-synthetic/test
new file mode 100644
index 000000000..4896f0dcc
--- /dev/null
+++ b/sbt/src/sbt-test/source-dependencies/naha-synthetic/test
@@ -0,0 +1,5 @@
+> compile
+
+$ copy-file changes/A.scala A.scala
+
+-> compile