diff --git a/src/stratifier.c b/src/stratifier.c
index 340440e6..8c63ed77 100644
--- a/src/stratifier.c
+++ b/src/stratifier.c
@@ -83,7 +83,13 @@ typedef struct pool_stats pool_stats_t;
 struct workbase {
 	/* Hash table data */
 	UT_hash_handle hh;
+
+	/* The next two fields need to be consecutive as both of them are
+	 * used as the key for their hashtable entry in remote_workbases */
 	int64_t id;
+	/* The client id this workinfo came from if remote */
+	int64_t client_id;
+
 	char idstring[20];
 
 	/* How many readers we currently have of this workbase, set
@@ -92,8 +98,6 @@ struct workbase {
 
 	/* The id a remote workinfo is mapped to locally */
 	int64_t mapped_id;
-	/* The client id this remote workinfo came from */
-	int64_t client_id;
 
 	ts_t gentime;
 	tv_t retired;
@@ -1748,6 +1752,14 @@ out:
 	return ret;
 }
 
+/* Remote workbases are keyed by the combined values of wb->id and
+ * wb->client_id to prevent collisions in the unlikely event two remote
+ * servers are generating the same workbase ids. */
+static void __add_to_remote_workbases(sdata_t *sdata, workbase_t *wb)
+{
+	HASH_ADD(hh, sdata->remote_workbases, id, sizeof(int64_t) * 2, wb);
+}
+
 static void check_incomplete_wbs(ckpool_t *ckp, sdata_t *sdata)
 {
 	workbase_t *wb, *tmp;
@@ -1769,7 +1781,7 @@ static void check_incomplete_wbs(ckpool_t *ckp, sdata_t *sdata)
 
 		/* Readd it to the hashlist */
 		ck_wlock(&sdata->workbase_lock);
-		HASH_ADD_I64(sdata->remote_workbases, id, wb);
+		__add_to_remote_workbases(sdata, wb);
 	}
 	ck_wunlock(&sdata->workbase_lock);
 
@@ -1810,7 +1822,7 @@ static void add_remote_base(ckpool_t *ckp, sdata_t *sdata, workbase_t *wb)
 			ck_wlock(&sdata->workbase_lock);
 		}
 	}
-	HASH_ADD_I64(sdata->remote_workbases, id, wb);
+	__add_to_remote_workbases(sdata, wb);
 	ck_wunlock(&sdata->workbase_lock);
 
 	val = generate_workinfo(ckp, wb, __func__);
@@ -2117,12 +2129,21 @@ static workbase_t *get_workbase(sdata_t *sdata, const int64_t id)
 	return wb;
 }
 
-static workbase_t *get_remote_workbase(sdata_t *sdata, const int64_t id)
+static workbase_t *__find_remote_workbase(sdata_t *sdata, const int64_t id, const int64_t client_id)
+{
+	int64_t lookup[2] = {id, client_id};
+	workbase_t *wb;
+
+	HASH_FIND(hh, sdata->remote_workbases, lookup, sizeof(int64_t) * 2, wb);
+	return wb;
+}
+
+static workbase_t *get_remote_workbase(sdata_t *sdata, const int64_t id, const int64_t client_id)
 {
 	workbase_t *wb;
 
 	ck_wlock(&sdata->workbase_lock);
-	HASH_FIND_I64(sdata->remote_workbases, &id, wb);
+	wb = __find_remote_workbase(sdata, id, client_id);
 	if (wb) {
 		if (wb->incomplete)
 			wb = NULL;
@@ -3681,7 +3702,7 @@ static json_t *user_stats(const user_instance_t *user)
 }
 
 /* Adjust workinfo id to virtual value for remote trusted workinfos */
-static void remap_workinfo_id(sdata_t *sdata, json_t *val)
+static void remap_workinfo_id(sdata_t *sdata, json_t *val, const int64_t client_id)
 {
 	int64_t mapped_id, id;
 	workbase_t *wb;
@@ -3689,7 +3710,7 @@ static void remap_workinfo_id(sdata_t *sdata, json_t *val)
 	json_get_int64(&id, val, "workinfoid");
 
 	ck_rlock(&sdata->workbase_lock);
-	HASH_FIND_I64(sdata->remote_workbases, &id, wb);
+	wb = __find_remote_workbase(sdata, id, client_id);
 	if (likely(wb))
 		mapped_id = wb->mapped_id;
 	else
@@ -6736,7 +6757,8 @@ static user_instance_t *generate_remote_user(ckpool_t *ckp, const char *workerna
 	return user;
 }
 
-static void parse_remote_share(ckpool_t *ckp, sdata_t *sdata, json_t *val, const char *buf)
+static void parse_remote_share(ckpool_t *ckp, sdata_t *sdata, json_t *val, const char *buf,
+			       const int64_t client_id)
 {
 	json_t *workername_val = json_object_get(val, "workername");
 	worker_instance_t *worker;
@@ -6784,12 +6806,13 @@ static void parse_remote_share(ckpool_t *ckp, sdata_t *sdata, json_t *val, const
 	val = json_deep_copy(val);
 	if (likely(user->secondaryuserid))
 		json_set_string(val, "secondaryuserid", user->secondaryuserid);
-	remap_workinfo_id(sdata, val);
+	remap_workinfo_id(sdata, val, client_id);
 
 	ckdbq_add(ckp, ID_SHARES, val);
 }
 
-static void parse_remote_shareerr(ckpool_t *ckp, sdata_t *sdata, json_t *val, const char *buf)
+static void parse_remote_shareerr(ckpool_t *ckp, sdata_t *sdata, json_t *val, const char *buf,
+				  const int64_t client_id)
 {
 	user_instance_t *user = NULL;
 	const char *workername;
@@ -6807,7 +6830,7 @@ static void parse_remote_shareerr(ckpool_t *ckp, sdata_t *sdata, json_t *val, co
 	val = json_deep_copy(val);
 	if (likely(user->secondaryuserid))
 		json_set_string(val, "secondaryuserid", user->secondaryuserid);
-	remap_workinfo_id(sdata, val);
+	remap_workinfo_id(sdata, val, client_id);
 
 	ckdbq_add(ckp, ID_SHAREERR, val);
 }
@@ -6981,7 +7004,7 @@ static void parse_remote_block(ckpool_t *ckp, sdata_t *sdata, json_t *val, const
 	json_get_double(&diff, val, "diff");
 
 	if (likely(id && coinbasehex && swaphex && cblen))
-		wb = get_remote_workbase(sdata, id);
+		wb = get_remote_workbase(sdata, id, client_id);
 
 	if (unlikely(!wb))
 		LOGWARNING("Inadequate data locally to attempt submit of remote block");
@@ -7016,7 +7039,7 @@ static void parse_remote_block(ckpool_t *ckp, sdata_t *sdata, json_t *val, const
 out_add:
 	/* Make a duplicate for use by ckdbq_add */
 	val = json_deep_copy(val);
-	remap_workinfo_id(sdata, val);
+	remap_workinfo_id(sdata, val, client_id);
 	if (!ckp->remote)
 		downstream_json(sdata, val, client_id, SSEND_PREPEND);
 
@@ -7170,7 +7193,7 @@ static void parse_trusted_msg(ckpool_t *ckp, sdata_t *sdata, json_t *val, stratu
 	}
 
 	if (likely(!safecmp(method, stratum_msgs[SM_SHARE])))
-		parse_remote_share(ckp, sdata, val, buf);
+		parse_remote_share(ckp, sdata, val, buf, client->id);
 	else if (!safecmp(method, stratum_msgs[SM_TRANSACTIONS]))
 		add_node_txns(ckp, sdata, val);
 	else if (!safecmp(method, stratum_msgs[SM_WORKERSTATS]))
@@ -7180,7 +7203,7 @@ static void parse_trusted_msg(ckpool_t *ckp, sdata_t *sdata, json_t *val, stratu
 	else if (!safecmp(method, stratum_msgs[SM_AUTH]))
 		parse_remote_auth(ckp, sdata, val, client, client->id);
 	else if (!safecmp(method, stratum_msgs[SM_SHAREERR]))
-		parse_remote_shareerr(ckp, sdata, val, buf);
+		parse_remote_shareerr(ckp, sdata, val, buf, client->id);
 	else if (!safecmp(method, stratum_msgs[SM_BLOCK]))
 		parse_remote_block(ckp, sdata, val, buf, client->id);
 	else if (!safecmp(method, stratum_msgs[SM_REQTXNS]))