diff --git a/src/ate/test_programs/dut_lib/dut_lib.cc b/src/ate/test_programs/dut_lib/dut_lib.cc
index d383ad02..f94d5f21 100644
--- a/src/ate/test_programs/dut_lib/dut_lib.cc
+++ b/src/ate/test_programs/dut_lib/dut_lib.cc
@@ -44,6 +44,8 @@ void OtLibTxCaSerialNums(void* transport, const uint8_t* spi_frame,
                          size_t spi_frame_size, uint64_t timeout_ms);
 void OtLibRxPersoBlob(void* transport, bool quiet, uint64_t timeout_ms,
                       size_t* num_objects, size_t* next_free, uint8_t* body);
+void OtLibTxPersoBlob(void* transport, const uint8_t* spi_frame,
+                      size_t spi_frame_size, uint64_t timeout_ms);
 }
 
 std::unique_ptr<DutLib> DutLib::Create(const std::string& fpga) {
@@ -145,5 +147,11 @@ void DutLib::DutRxFtPersoBlob(bool quiet, uint64_t timeout_ms, size_t* num_objs,
   OtLibRxPersoBlob(transport_, quiet, timeout_ms, num_objs, next_free, body);
 }
 
+void DutLib::DutTxFtPersoBlob(const uint8_t* spi_frame, size_t spi_frame_size,
+                              uint64_t timeout_ms) {
+  LOG(INFO) << "in DutLib::DutTxFtPersoBlob";
+  OtLibTxPersoBlob(transport_, spi_frame, spi_frame_size, timeout_ms);
+}
+
 }  // namespace test_programs
 }  // namespace provisioning
diff --git a/src/ate/test_programs/dut_lib/dut_lib.h b/src/ate/test_programs/dut_lib/dut_lib.h
index 3d817262..8dff4183 100644
--- a/src/ate/test_programs/dut_lib/dut_lib.h
+++ b/src/ate/test_programs/dut_lib/dut_lib.h
@@ -91,6 +91,12 @@ class DutLib {
    */
   void DutRxFtPersoBlob(bool quiet, uint64_t timeout_ms, size_t* num_objs,
                         size_t* next_free, uint8_t* body);
+  /**
+   * Calls opentitanlib methods to send the perso blob back to the DUT, which
+   * contains the TBS certificates to be endorsed.
+   */
+  void DutTxFtPersoBlob(const uint8_t* spi_frame, size_t spi_frame_size,
+                        uint64_t timeout_ms);
 
  private:
   // Must be 2x the opentitanlib UartConsole buffer size defined here:
diff --git a/src/ate/test_programs/ft.cc b/src/ate/test_programs/ft.cc
index c8d9f7b6..91e6d89f 100644
--- a/src/ate/test_programs/ft.cc
+++ b/src/ate/test_programs/ft.cc
@@ -340,7 +340,17 @@ int main(int argc, char **argv) {
     return -1;
   }
 
-  // TODO(timothytrippel): Send the endorsed certs back to the device.
+  // Send the endorsed certs back to the device.
+  perso_blob_t perso_blob_from_ate;
+  if (PackPersoBlob(num_tbs_certs, endorse_certs_responses,
+                    &perso_blob_from_ate) != 0) {
+    LOG(ERROR) << "Failed to repack the perso blob.";
+    return -1;
+  }
+  dut->DutTxFtPersoBlob(ca_serial_numbers_spi_frame.payload,
+                        ca_serial_numbers_spi_frame.cursor,
+                        /*timeout_ms=*/1000);
+
   // TODO(timothytrippel): Check the cert chains validate.
   // TODO(timothytrippel): Register the device.
 
diff --git a/src/ate/test_programs/otlib_wrapper/src/lib.rs b/src/ate/test_programs/otlib_wrapper/src/lib.rs
index f582c8a0..d39ccf57 100644
--- a/src/ate/test_programs/otlib_wrapper/src/lib.rs
+++ b/src/ate/test_programs/otlib_wrapper/src/lib.rs
@@ -706,7 +706,7 @@ pub extern "C" fn OtLibRxPersoBlob(
     // Receive the UJSON data payload from the DUT over the console.
     let timeout = Duration::from_millis(timeout_ms);
     let _ = UartConsole::wait_for(&spi_console, r"Exporting TBS certificates ...", timeout)
-        .expect("Perso blob device sync message missed.");
+        .expect("Perso blob device TX sync message missed.");
     let perso_blob = PersoBlob::recv(&spi_console, timeout, quiet, /*skip_crc=*/ true)
         .expect("Could not receive perso blob from DUT.");
     // SAFETY: the size pointers below should be a valid pointers to memory allocated by the caller.
@@ -718,3 +718,41 @@ pub extern "C" fn OtLibRxPersoBlob(
     body[..perso_blob.body.len()].copy_from_slice(perso_blob.body.as_slice());
     *next_free = perso_blob.next_free;
 }
+
+#[no_mangle]
+pub extern "C" fn OtLibTxPersoBlob(
+    transport: *const TransportWrapper,
+    spi_frame: *mut u8,
+    spi_frame_size: usize,
+    timeout_ms: u64,
+) {
+    // SAFETY: The transport wrapper pointer passed from C side should be the pointer returned by
+    // the call to `OtLibFpgaTransportInit(...)` above.
+    let transport: &TransportWrapper = unsafe { &*transport };
+
+    // SAFETY: spi_frame should be a valid pointer to memory allocated by the caller.
+    let spi_frame = unsafe { std::slice::from_raw_parts_mut(spi_frame, spi_frame_size) };
+
+    // Get handle to SPI console.
+    let spi = transport.spi("BOOTSTRAP").unwrap();
+    let device_console_tx_ready_pin = &transport.gpio_pin("IOA5").expect("Unable to get GPIO pin.");
+    let _ = device_console_tx_ready_pin.set_mode(PinMode::Input);
+    let _ = device_console_tx_ready_pin.set_pull_mode(PullMode::None);
+    let spi_console = SpiConsoleDevice::new(
+        &*spi,
+        Some(device_console_tx_ready_pin),
+        /*ignore_frame_num=*/ true,
+    )
+    .expect("Unable to create SPI console.");
+
+    // Send the UJSON data payload to the DUT over the console.
+    let _ = UartConsole::wait_for(
+        &spi_console,
+        r"Importing endorsed certificates ...\n",
+        Duration::from_millis(timeout_ms),
+    )
+    .expect("Perso blob device RX sync message missed.");
+    spi_console
+        .console_write(spi_frame.as_bytes())
+        .expect("Unable to write to console.");
+}