diff --git a/src/nfa/limex.h b/src/nfa/limex.h
index 3f1e49a3..2c429a67 100644
--- a/src/nfa/limex.h
+++ b/src/nfa/limex.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, Intel Corporation
+ * Copyright (c) 2015-2016, Intel Corporation
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -65,14 +65,13 @@ extern "C"
                                        void *state, u8 key);                   \
     char gf_name##_B_Reverse(const struct NFA *n, u64a offset, const u8 *buf,  \
                              size_t buflen, const u8 *hbuf, size_t hlen,       \
-                             struct hs_scratch *scratch, NfaCallback cb,       \
-                             void *context);                                   \
+                             NfaCallback cb, void *context);                   \
     char gf_name##_queueCompressState(const struct NFA *nfa,                   \
                                       const struct mq *q, s64a loc);           \
     char gf_name##_expandState(const struct NFA *nfa, void *dest,              \
                                const void *src, u64a offset, u8 key);          \
-    enum nfa_zombie_status gf_name##_zombie_status(const struct NFA *nfa,    \
-                                                   struct mq *q, s64a loc); \
+    enum nfa_zombie_status gf_name##_zombie_status(const struct NFA *nfa,      \
+                                                   struct mq *q, s64a loc);    \
     GENERATE_NFA_DUMP_DECL(gf_name)
 
 GENERATE_NFA_DECL(nfaExecLimEx32_1)
diff --git a/src/nfa/limex_runtime_impl.h b/src/nfa/limex_runtime_impl.h
index e362baef..011913f9 100644
--- a/src/nfa/limex_runtime_impl.h
+++ b/src/nfa/limex_runtime_impl.h
@@ -811,7 +811,6 @@ char JOIN(LIMEX_API_ROOT, _reportCurrent)(const struct NFA *n, struct mq *q) {
 char JOIN(LIMEX_API_ROOT, _B_Reverse)(const struct NFA *n, u64a offset,
                                       const u8 *buf, size_t buflen,
                                       const u8 *hbuf, size_t hlen,
-                                      UNUSED struct hs_scratch *scratch,
                                       NfaCallback cb, void *context) {
     assert(buf || hbuf);
     assert(buflen || hlen);
diff --git a/src/nfa/nfa_api.h b/src/nfa/nfa_api.h
index 84a5417b..84f5c4a0 100644
--- a/src/nfa/nfa_api.h
+++ b/src/nfa/nfa_api.h
@@ -44,7 +44,6 @@ extern "C"
 #include "callback.h"
 #include "ue2common.h"
 
-struct hs_scratch;
 struct mq;
 struct NFA;
 
@@ -212,16 +211,12 @@ char nfaQueueExecRose(const struct NFA *nfa, struct mq *q, ReportID report);
  * @param buflen length of buf
  * @param hbuf history buf
  * @param hlen length of hbuf
- * @param scratch scratch
  * @param callback the callback to call for each match raised
  * @param context context pointer passed to each callback
- *
- * Note: is NOT reentrant
  */
 char nfaBlockExecReverse(const struct NFA *nfa, u64a offset, const u8 *buf,
                          size_t buflen, const u8 *hbuf, size_t hlen,
-                         struct hs_scratch *scratch, NfaCallback callback,
-                         void *context);
+                         NfaCallback callback, void *context);
 
 /**
  * Check whether the given NFA's state indicates that it is in one or more
diff --git a/src/nfa/nfa_api_dispatch.c b/src/nfa/nfa_api_dispatch.c
index 0c765b36..fb27e4eb 100644
--- a/src/nfa/nfa_api_dispatch.c
+++ b/src/nfa/nfa_api_dispatch.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, Intel Corporation
+ * Copyright (c) 2015-2016, Intel Corporation
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -332,13 +332,12 @@ char nfaQueueExecRose(const struct NFA *nfa, struct mq *q, ReportID r) {
 
 char nfaBlockExecReverse(const struct NFA *nfa, u64a offset, const u8 *buf,
                          size_t buflen, const u8 *hbuf, size_t hlen,
-                         struct hs_scratch *scratch, NfaCallback callback,
-                         void *context) {
+                         NfaCallback callback, void *context) {
     assert(nfa);
     assert(ISALIGNED_CL(nfa) && ISALIGNED_CL(getImplNfa(nfa)));
 
     DISPATCH_BY_NFA_TYPE(_B_Reverse(nfa, offset, buf, buflen, hbuf, hlen,
-                                    scratch, callback, context));
+                                    callback, context));
     return 0;
 }
 
diff --git a/src/som/som_runtime.c b/src/som/som_runtime.c
index 84eeb601..fa996515 100644
--- a/src/som/som_runtime.c
+++ b/src/som/som_runtime.c
@@ -151,7 +151,7 @@ void runRevNfa(struct hs_scratch *scratch, const struct internal_report *ri,
     *from_offset = to_offset;
 
     nfaBlockExecReverse(nfa, to_offset, buf, buf_bytes, hbuf, history_bytes,
-                        scratch, somRevCallback, from_offset);
+                        somRevCallback, from_offset);
 
     assert(*from_offset <= to_offset);
 }
diff --git a/unit/internal/limex_nfa.cpp b/unit/internal/limex_nfa.cpp
index 47fd5d4a..679dc670 100644
--- a/unit/internal/limex_nfa.cpp
+++ b/unit/internal/limex_nfa.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, Intel Corporation
+ * Copyright (c) 2015-2016, Intel Corporation
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -369,7 +369,7 @@ TEST_P(LimExReverseTest, BlockExecReverse) {
     const size_t hlen = 0;
 
     nfaBlockExecReverse(nfa.get(), offset, buf, buflen, hbuf, hlen,
-                        scratch.get(), onMatch, &matches);
+                        onMatch, &matches);
 
     ASSERT_EQ(3, matches);
 }