diff --git a/firmware/common/radio.c b/firmware/common/radio.c
index b947cd62..36f65cad 100644
--- a/firmware/common/radio.c
+++ b/firmware/common/radio.c
@@ -60,7 +60,6 @@ void radio_init(radio_t* const radio)
 	radio->config[RADIO_BANK_TX][RADIO_OPMODE] = TRANSCEIVER_MODE_TX;
 	radio->config[RADIO_BANK_IDLE][RADIO_BIAS_TEE] = false;
 	radio->regs_dirty = 0;
-	radio->regs_locked = 0;
 }
 
 static inline void mark_dirty(radio_t* const radio, radio_register_t reg)
@@ -68,11 +67,6 @@ static inline void mark_dirty(radio_t* const radio, radio_register_t reg)
 	radio->regs_dirty |= (1 << reg);
 }
 
-static inline bool check_locked(radio_t* const radio, radio_register_t reg)
-{
-	return radio->regs_locked & (1 << reg);
-}
-
 radio_error_t radio_reg_write(
 	radio_t* const radio,
 	const radio_register_bank_t bank,
@@ -83,10 +77,6 @@ radio_error_t radio_reg_write(
 		return RADIO_ERR_INVALID_REGISTER;
 	}
 
-	if (check_locked(radio, reg)) {
-		return RADIO_ERR_LOCKED_REGISTER;
-	}
-
 	switch (bank) {
 	case RADIO_BANK_REQUESTED:
 		mark_dirty(radio, reg);
@@ -117,20 +107,6 @@ uint64_t radio_reg_read(
 	return radio->config[bank][reg];
 }
 
-radio_error_t radio_reg_lock(
-	radio_t* const radio,
-	const radio_register_t reg,
-	const bool locked)
-{
-	if (reg > RADIO_NUM_REGS) {
-		return RADIO_ERR_INVALID_REGISTER;
-	}
-
-	radio->regs_locked = (radio->regs_locked & ~(1 << reg)) | (locked << reg);
-
-	return RADIO_OK;
-}
-
 static uint32_t radio_update_direction(radio_t* const radio, uint64_t* bank)
 {
 	const uint64_t requested = bank[RADIO_OPMODE];
diff --git a/firmware/common/radio.h b/firmware/common/radio.h
index caaa222d..8e12471a 100644
--- a/firmware/common/radio.h
+++ b/firmware/common/radio.h
@@ -34,7 +34,6 @@ typedef enum {
 	RADIO_ERR_INVALID_PARAM = -2,
 	RADIO_ERR_INVALID_BANK = -3,
 	RADIO_ERR_INVALID_REGISTER = -4,
-	RADIO_ERR_LOCKED_REGISTER = -5,
 	RADIO_ERR_UNSUPPORTED_OPERATION = -10,
 	RADIO_ERR_UNIMPLEMENTED = -19,
 	RADIO_ERR_OTHER = -9999,
@@ -232,7 +231,6 @@ typedef struct {
 	radio_config_mode_t config_mode;
 	uint64_t config[RADIO_NUM_BANKS][RADIO_NUM_REGS];
 	volatile uint32_t regs_dirty;
-	uint32_t regs_locked;
 	update_fn update_cb;
 } radio_t;
 
@@ -256,15 +254,6 @@ uint64_t radio_reg_read(
 	const radio_register_bank_t bank,
 	const radio_register_t reg);
 
-/**
- * Lock a register. Prevents any future calls to `radio_reg_write`
- * from overwriting the current stored value of the register.
- */
-radio_error_t radio_reg_lock(
-	radio_t* const radio,
-	const radio_register_t reg,
-	const bool locked);
-
 /**
  * Apply changes requested in RADIO_BANK_REQUESTED.
  * Return true if any changes were applied.
diff --git a/firmware/hackrf_usb/hackrf_usb.c b/firmware/hackrf_usb/hackrf_usb.c
index 4cdfbd14..813a9453 100644
--- a/firmware/hackrf_usb/hackrf_usb.c
+++ b/firmware/hackrf_usb/hackrf_usb.c
@@ -182,7 +182,6 @@ static usb_request_handler_fn vendor_request_handler[] = {
 	usb_vendor_request_write_radio_reg,
 	usb_vendor_request_read_radio_reg,
 	usb_vendor_request_get_buffer_size,
-	usb_vendor_request_lock_radio_reg,
 };
 
 static const uint32_t vendor_request_handler_count =
diff --git a/firmware/hackrf_usb/usb_api_register.c b/firmware/hackrf_usb/usb_api_register.c
index a46a2240..626c7508 100644
--- a/firmware/hackrf_usb/usb_api_register.c
+++ b/firmware/hackrf_usb/usb_api_register.c
@@ -416,20 +416,3 @@ usb_request_status_t usb_vendor_request_read_radio_reg(
 	}
 	return USB_REQUEST_STATUS_OK;
 }
-
-usb_request_status_t usb_vendor_request_lock_radio_reg(
-	usb_endpoint_t* const endpoint,
-	const usb_transfer_stage_t stage)
-{
-	if (stage == USB_TRANSFER_STAGE_SETUP) {
-		uint8_t reg = endpoint->setup.index;
-		bool locked = endpoint->setup.value != 0 ? true : false;
-		if (reg >= RADIO_NUM_REGS) {
-			return USB_REQUEST_STATUS_STALL;
-		}
-		radio_reg_lock(&radio, reg, locked);
-		usb_transfer_schedule_ack(endpoint->in);
-	}
-
-	return USB_REQUEST_STATUS_OK;
-}
diff --git a/firmware/hackrf_usb/usb_api_register.h b/firmware/hackrf_usb/usb_api_register.h
index 7e434c1a..a5a36550 100644
--- a/firmware/hackrf_usb/usb_api_register.h
+++ b/firmware/hackrf_usb/usb_api_register.h
@@ -70,6 +70,3 @@ usb_request_status_t usb_vendor_request_write_radio_reg(
 usb_request_status_t usb_vendor_request_read_radio_reg(
 	usb_endpoint_t* const endpoint,
 	const usb_transfer_stage_t stage);
-usb_request_status_t usb_vendor_request_lock_radio_reg(
-	usb_endpoint_t* const endpoint,
-	const usb_transfer_stage_t stage);
diff --git a/firmware/hackrf_usb/usb_descriptor.c b/firmware/hackrf_usb/usb_descriptor.c
index 726e126a..dde22e6e 100644
--- a/firmware/hackrf_usb/usb_descriptor.c
+++ b/firmware/hackrf_usb/usb_descriptor.c
@@ -28,7 +28,7 @@
 
 #define USB_VENDOR_ID (0x1D50)
 
-#define USB_API_VERSION (0x0114)
+#define USB_API_VERSION (0x0113)
 
 #define USB_WORD(x) (x & 0xFF), ((x >> 8) & 0xFF)
 
diff --git a/host/hackrf-tools/src/hackrf_debug.c b/host/hackrf-tools/src/hackrf_debug.c
index 475130eb..5f8785b5 100644
--- a/host/hackrf-tools/src/hackrf_debug.c
+++ b/host/hackrf-tools/src/hackrf_debug.c
@@ -545,30 +545,6 @@ int radio_write_register(
 	return result;
 }
 
-int radio_lock_register(
-	hackrf_device* device,
-	const uint16_t register_number,
-	const bool register_locked)
-{
-	int result = HACKRF_SUCCESS;
-	result = hackrf_radio_lock_register(
-		device,
-		(uint8_t) register_number,
-		register_locked);
-
-	if (result == HACKRF_SUCCESS) {
-		printf("register [%2d] -> %s\n",
-		       register_number,
-		       register_locked ? "locked" : "unlocked");
-	} else {
-		printf("hackrf_radio_lock_register() failed: %s (%d)\n",
-		       hackrf_error_name(result),
-		       result);
-	}
-
-	return result;
-}
-
 int read_register(
 	hackrf_device* device,
 	uint8_t part,
@@ -645,20 +621,6 @@ int write_register(
 	return HACKRF_ERROR_INVALID_PARAM;
 }
 
-int lock_register(
-	hackrf_device* device,
-	uint8_t part,
-	const uint16_t register_number,
-	const bool register_locked)
-{
-	switch (part) {
-	case PART_RADIO:
-		return radio_lock_register(device, register_number, register_locked);
-	default:
-		return HACKRF_ERROR_INVALID_PARAM;
-	}
-}
-
 static const char* mode_name(uint32_t mode)
 {
 	const char* mode_names[] = {"IDLE", "WAIT", "RX", "TX_START", "TX_RUN"};
@@ -713,7 +675,6 @@ static void usage()
 	printf("\t-n, --register <n>: set register number for read/write operations\n");
 	printf("\t-r, --read: read register specified by last -n argument, or all registers\n");
 	printf("\t-w, --write <v>: write register specified by last -n argument with value <v>\n");
-	printf("\t-L, --lock <state>: lock register specified by last -n argument (0 for unlocked, 1 for locked)\n");
 	printf("\t-c, --config: print SI5351C multisynth configuration information\n");
 	printf("\t-d, --device <s>: specify a particular device by serial number\n");
 	printf("\t-m, --max283x: target MAX283x\n");
@@ -748,7 +709,6 @@ static struct option long_options[] = {
 	{"register", required_argument, 0, 'n'},
 	{"write", required_argument, 0, 'w'},
 	{"read", no_argument, 0, 'r'},
-	{"lock", required_argument, 0, 'L'},
 	{"device", required_argument, 0, 'd'},
 	{"help", no_argument, 0, 'h'},
 	{"max2837", no_argument, 0, 'm'},
@@ -780,12 +740,10 @@ int main(int argc, char** argv)
 	int bank = -1;
 	uint64_t register_number = REGISTER_INVALID;
 	uint64_t register_value;
-	uint64_t register_locked;
 	hackrf_device* device = NULL;
 	int option_index = 0;
 	bool read = false;
 	bool write = false;
-	bool lock = false;
 	bool dump_config = false;
 	bool dump_state = false;
 	uint8_t part = PART_NONE;
@@ -824,7 +782,7 @@ int main(int argc, char** argv)
 	while ((opt = getopt_long(
 			argc,
 			argv,
-			"b:n:rw:l:d:cmsfgi1:2:C:N:P:ST:R:h?u:l:ta:o",
+			"b:n:rw:d:cmsfgi1:2:C:N:P:ST:R:h?u:l:ta:o",
 			long_options,
 			&option_index)) != EOF) {
 		switch (opt) {
@@ -847,11 +805,6 @@ int main(int argc, char** argv)
 			read = true;
 			break;
 
-		case 'L':
-			lock = true;
-			result = parse_int(optarg, &register_locked);
-			break;
-
 		case 'c':
 			dump_config = true;
 			break;
@@ -978,8 +931,8 @@ int main(int argc, char** argv)
 		}
 	}
 
-	if ((write && read) || (lock && write) || (lock && read)) {
-		fprintf(stderr, "Read, write and lock options are mutually exclusive.\n");
+	if (write && read) {
+		fprintf(stderr, "Read and write options are mutually exclusive.\n");
 		usage();
 		return EXIT_FAILURE;
 	}
@@ -996,10 +949,6 @@ int main(int argc, char** argv)
 		return EXIT_FAILURE;
 	}
 
-	if (lock && part != PART_RADIO) {
-		fprintf(stderr, "Lock option is only valid for radio.\n");
-	}
-
 	if ((bank > -1) && (part != PART_RADIO)) {
 		fprintf(stderr, "Bank valid only for radio.\n");
 		usage();
@@ -1010,11 +959,11 @@ int main(int argc, char** argv)
 		bank = 0;
 	}
 
-	if (!(write || read || lock || dump_config || dump_state || set_tx_limit ||
+	if (!(write || read || dump_config || dump_state || set_tx_limit ||
 	      set_rx_limit || set_ui || set_leds || set_p1 || set_p2 || set_clkin ||
 	      set_narrowband || set_fpga_bitstream || read_selftest || test_rtc_osc ||
 	      read_adc)) {
-		fprintf(stderr, "Specify read, write, lock, or config option.\n");
+		fprintf(stderr, "Specify read, write, or config option.\n");
 		usage();
 		return EXIT_FAILURE;
 	}
@@ -1067,10 +1016,6 @@ int main(int argc, char** argv)
 		}
 	}
 
-	if (lock) {
-		result = lock_register(device, part, register_number, register_locked);
-	}
-
 	if (dump_config) {
 		si5351c_read_configuration(device);
 	}
diff --git a/host/libhackrf/src/hackrf.c b/host/libhackrf/src/hackrf.c
index eab5bfe7..4018ac63 100644
--- a/host/libhackrf/src/hackrf.c
+++ b/host/libhackrf/src/hackrf.c
@@ -121,7 +121,6 @@ typedef enum {
 	HACKRF_VENDOR_REQUEST_RADIO_WRITE_REG = 59,
 	HACKRF_VENDOR_REQUEST_RADIO_READ_REG = 60,
 	HACKRF_VENDOR_REQUEST_GET_BUFFER_SIZE = 61,
-	HACKRF_VENDOR_REQUEST_RADIO_LOCK_REG = 62,
 } hackrf_vendor_request;
 
 #define USB_CONFIG_STANDARD 0x1
@@ -3576,33 +3575,6 @@ int ADDCALL hackrf_radio_write_register(
 	}
 }
 
-int ADDCALL hackrf_radio_lock_register(
-	hackrf_device* device,
-	const uint8_t register_number,
-	const bool register_locked)
-{
-	USB_API_REQUIRED(device, 0x0114);
-	int result;
-
-	result = libusb_control_transfer(
-		device->usb_device,
-		LIBUSB_ENDPOINT_OUT | LIBUSB_REQUEST_TYPE_VENDOR |
-			LIBUSB_RECIPIENT_DEVICE,
-		HACKRF_VENDOR_REQUEST_RADIO_LOCK_REG,
-		register_locked,
-		register_number,
-		NULL,
-		0,
-		DEFAULT_REQUEST_TIMEOUT);
-
-	if (result != 0) {
-		last_libusb_error = result;
-		return HACKRF_ERROR_LIBUSB;
-	}
-
-	return HACKRF_SUCCESS;
-}
-
 #ifdef __cplusplus
 } // __cplusplus defined.
 #endif
diff --git a/host/libhackrf/src/hackrf.h b/host/libhackrf/src/hackrf.h
index 6cf71dd9..eeca65e0 100644
--- a/host/libhackrf/src/hackrf.h
+++ b/host/libhackrf/src/hackrf.h
@@ -2385,20 +2385,6 @@ extern ADDAPI int ADDCALL hackrf_radio_write_register(
 	const uint8_t register_number,
 	const uint64_t value);
 
-/**
- * Lock or unlock a radio configuration register.
- *
- * @param[in] device device to write
- * @param[in] register_number register number to mask
- * @param[out] locked locked state for the register
- * @return @ref HACKRF_SUCCESS on success or @ref hackrf_error variant
- * @ingroup debug
- */
-extern ADDAPI int ADDCALL hackrf_radio_lock_register(
-	hackrf_device* device,
-	const uint8_t register_number,
-	const bool register_locked);
-
 #ifdef __cplusplus
 } // __cplusplus defined.
 #endif