diff --git a/spine-as3/spine-as3/src/spine/Bone.as b/spine-as3/spine-as3/src/spine/Bone.as
index ce1255b2f..fa1497e96 100644
--- a/spine-as3/spine-as3/src/spine/Bone.as
+++ b/spine-as3/spine-as3/src/spine/Bone.as
@@ -273,8 +273,8 @@ public class Bone implements Updatable {
 		var x:Number = world[0] - _worldX, y:Number = world[1] - _worldY;
 		var a:Number = _a, b:Number = _b, c:Number = _c, d:Number = _d;
 		var invDet:Number = 1 / (a * d - b * c);
-		world[0] = (x * a * invDet - y * b * invDet);
-		world[1] = (y * d * invDet - x * c * invDet);
+		world[0] = (x * d * invDet - y * b * invDet);
+		world[1] = (y * a * invDet - x * c * invDet);
 	}
 
 	public function localToWorld (local:Vector.<Number>) : void {
diff --git a/spine-c/src/spine/Bone.c b/spine-c/src/spine/Bone.c
index 89d3cee0e..f7f92c1b7 100644
--- a/spine-c/src/spine/Bone.c
+++ b/spine-c/src/spine/Bone.c
@@ -221,8 +221,8 @@ void spBone_worldToLocal (spBone* self, float worldX, float worldY, float* local
 	float x = worldX - self->worldX, y = worldY - self->worldY;
 	float a = self->a, b = self->b, c = self->c, d = self->d;
 	float invDet = 1 / (a * d - b * c);
-	*localX = (x * a * invDet - y * b * invDet);
-	*localY = (y * d * invDet - x * c * invDet);
+	*localX = (x * d * invDet - y * b * invDet);
+	*localY = (y * a * invDet - x * c * invDet);
 }
 
 void spBone_localToWorld (spBone* self, float localX, float localY, float* worldX, float* worldY) {
diff --git a/spine-csharp/src/Bone.cs b/spine-csharp/src/Bone.cs
index ed53caf47..9ab20166c 100644
--- a/spine-csharp/src/Bone.cs
+++ b/spine-csharp/src/Bone.cs
@@ -233,8 +233,8 @@ namespace Spine {
 			float x = worldX - this.worldX, y = worldY - this.worldY;
 			float a = this.a, b = this.b, c = this.c, d = this.d;
 			float invDet = 1 / (a * d - b * c);
-			localX = (x * a * invDet - y * b * invDet);
-			localY = (y * d * invDet - x * c * invDet);
+			localX = (x * d * invDet - y * b * invDet);
+			localY = (y * a * invDet - x * c * invDet);
 		}
 
 		public void LocalToWorld (float localX, float localY, out float worldX, out float worldY) {
diff --git a/spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/Bone.java b/spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/Bone.java
index cc7b5c0e6..1248839e8 100644
--- a/spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/Bone.java
+++ b/spine-libgdx/spine-libgdx/src/com/esotericsoftware/spine/Bone.java
@@ -356,8 +356,8 @@ public class Bone implements Updatable {
 		float x = world.x - worldX, y = world.y - worldY;
 		float a = this.a, b = this.b, c = this.c, d = this.d;
 		float invDet = 1 / (a * d - b * c);
-		world.x = (x * a * invDet - y * b * invDet);
-		world.y = (y * d * invDet - x * c * invDet);
+		world.x = (x * d * invDet - y * b * invDet);
+		world.y = (y * a * invDet - x * c * invDet);
 		return world;
 	}