diff --git a/sys/include/net/gnrc/sixlowpan/config.h b/sys/include/net/gnrc/sixlowpan/config.h
index 90cd46b559..ac0cd47bb8 100644
--- a/sys/include/net/gnrc/sixlowpan/config.h
+++ b/sys/include/net/gnrc/sixlowpan/config.h
@@ -97,6 +97,21 @@ extern "C" {
 #define GNRC_SIXLOWPAN_FRAG_RBUF_AGGRESSIVE_OVERRIDE    (1)
 #endif
 
+/**
+ * @brief   Deletion timer for reassembly buffer entries in microseconds
+ *
+ * @note    Only applicable with
+ *          [gnrc_sixlowpan_frag_rb](@ref net_gnrc_sixlowpan_frag_rb) module
+ *
+ * Time to pass between completion of a datagram and the deletion of its
+ * reassembly buffer entry. If this value is 0, the entry is dropped
+ * immediately. Use this value to prevent re-creation of a reassembly buffer
+ * entry on late arriving link-layer duplicates.
+ */
+#ifndef GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER
+#define GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER              (0U)
+#endif
+
 /**
  * @brief   Registration lifetime in minutes for the address registration option
  *
diff --git a/sys/net/gnrc/network_layer/sixlowpan/frag/rb/gnrc_sixlowpan_frag_rb.c b/sys/net/gnrc/network_layer/sixlowpan/frag/rb/gnrc_sixlowpan_frag_rb.c
index c4faefa724..7a08aee543 100644
--- a/sys/net/gnrc/network_layer/sixlowpan/frag/rb/gnrc_sixlowpan_frag_rb.c
+++ b/sys/net/gnrc/network_layer/sixlowpan/frag/rb/gnrc_sixlowpan_frag_rb.c
@@ -21,6 +21,7 @@
 #include "net/ipv6/hdr.h"
 #include "net/gnrc.h"
 #include "net/gnrc/sixlowpan.h"
+#include "net/gnrc/sixlowpan/config.h"
 #ifdef  MODULE_GNRC_SIXLOWPAN_FRAG_VRB
 #include "net/gnrc/sixlowpan/frag/vrb.h"
 #endif  /* MODULE_GNRC_SIXLOWPAN_FRAG_VRB */
@@ -115,7 +116,7 @@ static int _check_fragments(gnrc_sixlowpan_frag_rb_base_t *entry,
         }
         /* End was already checked in overlap check */
         if (ptr->start == offset) {
-            DEBUG("6lo rbuf: fragment already in reassembly buffer");
+            DEBUG("6lo rbuf: fragment already in reassembly buffer\n");
             return RBUF_ADD_DUPLICATE;
         }
         ptr = ptr->next;
@@ -360,6 +361,18 @@ static bool _rbuf_update_ints(gnrc_sixlowpan_frag_rb_base_t *entry,
     return true;
 }
 
+static void _gc_pkt(gnrc_sixlowpan_frag_rb_t *rbuf)
+{
+#if GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER > 0
+    if (rbuf->super.current_size == 0) {
+        /* packet is scheduled for deletion, but was complete, i.e. pkt is
+         * already handed up to other layer, i.e. no need to release */
+        return;
+    }
+#endif
+    gnrc_pktbuf_release(rbuf->pkt);
+}
+
 void gnrc_sixlowpan_frag_rb_gc(void)
 {
     uint32_t now_usec = xtimer_now_usec();
@@ -380,7 +393,7 @@ void gnrc_sixlowpan_frag_rb_gc(void)
                                          l2addr_str),
                   (unsigned)rbuf[i].super.datagram_size, rbuf[i].super.tag);
 
-            gnrc_pktbuf_release(rbuf[i].pkt);
+            _gc_pkt(&rbuf[i]);
             gnrc_sixlowpan_frag_rb_remove(&(rbuf[i]));
         }
     }
@@ -419,6 +432,14 @@ static int _rbuf_get(const void *src, size_t src_len,
                                          rbuf[i].super.dst_len,
                                          l2addr_str),
                   (unsigned)rbuf[i].super.datagram_size, rbuf[i].super.tag);
+#if GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER > 0
+            if (rbuf[i].super.current_size == 0) {
+                /* ensure that only empty reassembly buffer entries and entries
+                 * scheduled for deletion have `current_size == 0` */
+                DEBUG("6lo rfrag: scheduled for deletion, don't add fragment\n");
+                return -1;
+            }
+#endif
             rbuf[i].super.arrival = now_usec;
             _set_rbuf_timeout();
             return i;
@@ -514,7 +535,7 @@ void gnrc_sixlowpan_frag_rb_reset(void)
     for (unsigned int i = 0; i < GNRC_SIXLOWPAN_FRAG_RBUF_SIZE; i++) {
         if ((rbuf[i].pkt != NULL) &&
             (rbuf[i].pkt->users > 0)) {
-            gnrc_pktbuf_release(rbuf[i].pkt);
+            _gc_pkt(&rbuf[i]);
         }
     }
     memset(rbuf, 0, sizeof(rbuf));
@@ -539,6 +560,25 @@ void gnrc_sixlowpan_frag_rb_base_rm(gnrc_sixlowpan_frag_rb_base_t *entry)
     entry->datagram_size = 0;
 }
 
+static void _tmp_rm(gnrc_sixlowpan_frag_rb_t *rbuf)
+{
+#if GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER > 0U
+        /* use garbage-collection to leave the entry for at least
+         * GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER in the reassembly buffer by
+         * setting the arrival time to
+         * (GNRC_SIXLOWPAN_FRAG_RBUF_TIMEOUT_US - GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER)
+         * microseconds in the past */
+        rbuf->super.arrival = xtimer_now_usec() -
+                              (GNRC_SIXLOWPAN_FRAG_RBUF_TIMEOUT_US -
+                               GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER);
+        /* reset current size to prevent late duplicates to trigger another
+         * dispatch */
+        rbuf->super.current_size = 0;
+#else   /* GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER == 0U */
+        gnrc_sixlowpan_frag_rb_remove(rbuf);
+#endif  /* GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER */
+}
+
 int gnrc_sixlowpan_frag_rb_dispatch_when_complete(gnrc_sixlowpan_frag_rb_t *rbuf,
                                                    gnrc_netif_hdr_t *netif_hdr)
 {
@@ -555,7 +595,7 @@ int gnrc_sixlowpan_frag_rb_dispatch_when_complete(gnrc_sixlowpan_frag_rb_t *rbuf
         if (netif == NULL) {
             DEBUG("6lo rbuf: error allocating netif header\n");
             gnrc_pktbuf_release(rbuf->pkt);
-            gnrc_sixlowpan_frag_rb_remove(rbuf);
+            _tmp_rm(rbuf);
             return -1;
         }
 
@@ -570,7 +610,7 @@ int gnrc_sixlowpan_frag_rb_dispatch_when_complete(gnrc_sixlowpan_frag_rb_t *rbuf
         new_netif_hdr->rssi = netif_hdr->rssi;
         LL_APPEND(rbuf->pkt, netif);
         gnrc_sixlowpan_dispatch_recv(rbuf->pkt, NULL, 0);
-        gnrc_sixlowpan_frag_rb_remove(rbuf);
+        _tmp_rm(rbuf);
     }
     return res;
 }