diff --git a/src/main/tjava/com/r35157/libs/jupiter/perps/impl/anchoridl/AnchorIdlJupiterPerpsPositionDecoder.tjava b/src/main/tjava/com/r35157/libs/jupiter/perps/impl/anchoridl/AnchorIdlJupiterPerpsPositionDecoder.tjava
index e1567ef..096af67 100644
--- a/src/main/tjava/com/r35157/libs/jupiter/perps/impl/anchoridl/AnchorIdlJupiterPerpsPositionDecoder.tjava
+++ b/src/main/tjava/com/r35157/libs/jupiter/perps/impl/anchoridl/AnchorIdlJupiterPerpsPositionDecoder.tjava
@@ -47,13 +47,16 @@ class AnchorIdlJupiterPerpsPositionDecoder {
     private JupiterPerpsPositionDirection decodeDirection(
             byte rawSide
     ) {
-        return switch (rawSide) {
-            case 0 -> JupiterPerpsPositionDirection.LONG;
-            case 1 -> JupiterPerpsPositionDirection.SHORT;
+        // Jupiter Perps position side values are encoded as 1 = LONG, 2 = SHORT.
+        JupiterPerpsPositionDirection direction = switch (rawSide) {
+            case 1 -> JupiterPerpsPositionDirection.LONG;
+            case 2 -> JupiterPerpsPositionDirection.SHORT;
             default -> throw new IllegalArgumentException(
                     "Unknown Jupiter Perps position side: " + rawSide
             );
         };
+
+        return direction;
     }
 
     private static final int ANCHOR_DISCRIMINATOR_LENGTH = 8;