diff --git a/src/core/pbuf.c b/src/core/pbuf.c
index ef6812c9..0b5af7c5 100644
--- a/src/core/pbuf.c
+++ b/src/core/pbuf.c
@@ -1125,13 +1125,11 @@ pbuf_take_at(struct pbuf *buf, const void *dataptr, u16_t len, u16_t offset)
   if ((q != NULL) && (q->tot_len >= target_offset + len)) {
     u16_t remaining_len = len;
     const u8_t* src_ptr = (const u8_t*)dataptr;
-    if (target_offset > 0) {
-      /* copy the part that goes into the first pbuf */
-      u16_t first_copy_len = LWIP_MIN(q->len - target_offset, len);
-      MEMCPY(((u8_t*)q->payload) + target_offset, dataptr, first_copy_len);
-      remaining_len -= first_copy_len;
-      src_ptr += first_copy_len;
-    }
+    /* copy the part that goes into the first pbuf */
+    u16_t first_copy_len = LWIP_MIN(q->len - target_offset, len);
+    MEMCPY(((u8_t*)q->payload) + target_offset, dataptr, first_copy_len);
+    remaining_len -= first_copy_len;
+    src_ptr += first_copy_len;
     if (remaining_len > 0) {
       return pbuf_take(q->next, src_ptr, remaining_len);
     }
diff --git a/test/unit/core/test_pbuf.c b/test/unit/core/test_pbuf.c
index 211465ec..8711136c 100644
--- a/test/unit/core/test_pbuf.c
+++ b/test/unit/core/test_pbuf.c
@@ -139,6 +139,86 @@ START_TEST(test_pbuf_queueing_bigger_than_64k)
 }
 END_TEST
 
+/* Test for bug that writing with pbuf_take_at() did nothing
+ * and returned ERR_OK when writing at beginning of a pbuf
+ * in the chain.
+ */
+START_TEST(test_pbuf_take_at_edge)
+{
+  err_t res;
+  u8_t *out;
+  int i;
+  u8_t testdata[] = { 0x01, 0x08, 0x82, 0x02 };
+  struct pbuf *p = pbuf_alloc(PBUF_RAW, 1024, PBUF_POOL);
+  struct pbuf *q = p->next;
+  /* alloc big enough to get a chain of pbufs */
+  fail_if(p->tot_len == p->len);
+  memset(p->payload, 0, p->len);
+  memset(q->payload, 0, q->len);
+
+  /* copy data to the beginning of first pbuf */
+  res = pbuf_take_at(p, &testdata, sizeof(testdata), 0);
+  fail_unless(res == ERR_OK);
+
+  out = p->payload;
+  for (i = 0; i < sizeof(testdata); i++) {
+    fail_unless(out[i] == testdata[i],
+      "Bad data at pos %d, was %02X, expected %02X", i, out[i], testdata[i]);
+  }
+
+  /* copy data to the just before end of first pbuf */
+  res = pbuf_take_at(p, &testdata, sizeof(testdata), p->len - 1);
+  fail_unless(res == ERR_OK);
+
+  out = p->payload;
+  fail_unless(out[p->len - 1] == testdata[0],
+    "Bad data at pos %d, was %02X, expected %02X", p->len - 1, out[p->len - 1], testdata[0]);
+  out = q->payload;
+  for (i = 1; i < sizeof(testdata); i++) {
+    fail_unless(out[i-1] == testdata[i],
+      "Bad data at pos %d, was %02X, expected %02X", p->len - 1 + i, out[i-1], testdata[i]);
+  }
+
+  /* copy data to the beginning of second pbuf */
+  res = pbuf_take_at(p, &testdata, sizeof(testdata), p->len);
+  fail_unless(res == ERR_OK);
+
+  out = p->payload;
+  for (i = 0; i < sizeof(testdata); i++) {
+    fail_unless(out[i] == testdata[i],
+      "Bad data at pos %d, was %02X, expected %02X", p->len+i, out[i], testdata[i]);
+  }
+}
+END_TEST
+
+/* Verify pbuf_put_at()/pbuf_get_at() when using
+ * offsets equal to beginning of new pbuf in chain
+ */
+START_TEST(test_pbuf_get_put_at_edge)
+{
+  u8_t *out;
+  u8_t testdata = 0x01;
+  u8_t getdata;
+  struct pbuf *p = pbuf_alloc(PBUF_RAW, 1024, PBUF_POOL);
+  struct pbuf *q = p->next;
+  /* alloc big enough to get a chain of pbufs */
+  fail_if(p->tot_len == p->len);
+  memset(p->payload, 0, p->len);
+  memset(q->payload, 0, q->len);
+
+  /* put byte at the beginning of second pbuf */
+  pbuf_put_at(p, p->len, testdata);
+
+  out = q->payload;
+  fail_unless(*out == testdata,
+    "Bad data at pos %d, was %02X, expected %02X", p->len, *out, testdata);
+
+  getdata = pbuf_get_at(p, p->len);
+  fail_unless(*out == getdata,
+    "pbuf_get_at() returned bad data at pos %d, was %02X, expected %02X", p->len, getdata, *out);
+}
+END_TEST
+
 /** Create the suite including all tests for this module */
 Suite *
 pbuf_suite(void)
@@ -146,7 +226,9 @@ pbuf_suite(void)
   testfunc tests[] = {
     TESTFUNC(test_pbuf_copy_zero_pbuf),
     TESTFUNC(test_pbuf_split_64k_on_small_pbufs),
-    TESTFUNC(test_pbuf_queueing_bigger_than_64k)
+    TESTFUNC(test_pbuf_queueing_bigger_than_64k),
+    TESTFUNC(test_pbuf_take_at_edge),
+    TESTFUNC(test_pbuf_get_put_at_edge)
   };
   return create_suite("PBUF", tests, sizeof(tests)/sizeof(testfunc), pbuf_setup, pbuf_teardown);
 }