# US 10,375,248 B2 · Call authentication using call forwarding

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- Number: US 10,375,248 B2
- Document ID: US10375248B2
- Status: Granted
- Kind: B2
- Application number: 16/026,498
- Filed: 2018-07-03
- Published: 2018-11-15
- Granted: 2019-08-06
- Earliest claimed: 2016-08-03
- Assignees: Pindrop Security, Inc.
- Applicants: Pindrop Security, Inc.
- Inventors: Payas Gupta; David Dewey
- Web page: https://patentgrep.com/patent/US10375248B2

## CPC

- H04W 12/126: Anti-theft arrangements, e.g. protection against subscriber identity module [SIM] cloning
- H04L 67/02: based on web technology, e.g. hypertext transfer protocol [HTTP]
- H04M 3/436: Arrangements for screening incoming calls {, i.e. evaluating the characteristics of a call before deciding whether to answer it (based on the calling party profile H04M3/42059; based on location H04M3/42348; based on presence H04M3/42365; diversion H04M3/54)}
- H04M 3/54: Arrangements for diverting calls for one subscriber to another predetermined subscriber {(based on the calling party profile H04M3/42059; based on location H04M3/42348; based on presence H04M3/42365; to voice mail H04M3/53308)}
- H04M 3/543: {Call deflection}
- H04W 4/16: Communication-related supplementary services, e.g. call-transfer or call-hold
- H04W 4/50: Service provisioning or reconfiguring
- H04W 12/06: Authentication
- H04L 63/00: {Network architectures or network communication protocols for network security (cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00; network architectures or network communication protocols for wireless network security H04W12/00; security arrangements for protecting computers or computer systems against unauthorised activity G06F21/00)}
- H04L 63/126: {the source of the received data}
- H04L 63/1466: {Active attacks involving interception, injection, modification, spoofing of data unit addresses, e.g. hijacking, packet injection or TCP sequence number attacks}
- H04M 3/42059: {Making use of the calling party identifier}
- H04M 2203/6027: Fraud preventions
- H04M 2203/6045: Identity confirmation
- H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72)
- H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M)
- H04M: TELEPHONIC COMMUNICATION (circuits for controlling other apparatus via a telephone cable and not involving telephone switching apparatus G08)

## Abstract

The invention may verify calls to a telephone device by activating call forwarding to redirect calls for the telephone device to a prescribed destination; receiving a message from a server verifying the call; deactivating call forwarding to receive the call; and reactivating call forwarding when the call is concluded. In another embodiment, the invention may, in response to a telephone device initiating a call to a second telephone device installed with a particular application or software, transmit a message to a server causing it to instruct the second telephone device to deactivate call forwarding. In yet another embodiment, the invention may cause a server to receive a message from a prescribed location indicating that a call was received via call forwarding, and in response to the message, transmit an instruction to the intended recipient to deactivate the call forwarding if the call is verified as legitimate.

## Claims

### Claim 1

A method implemented in a server comprising:
executing by a processor in said server,
receiving, from a prescribed location, a message indicating that said prescribed location has received, by virtue of call forwarding, a telephone call made by a first telephone device to a particular telephone number assigned to a second telephone device, said call forwarding being activated by a particular application or software executing on said second telephone device; and
in response to receiving said message, transmitting an instruction to said second telephone device to deactivate said call forwarding, allowing the second telephone device to receive the telephone call when:
said server has received, by a predetermined time relative to receiving said message, a notification from said first telephone device of said telephone call, or
said server has verified said telephone call as legitimate.

### Claim 2 (depends on 1)

The method of claim 1, wherein said prescribed location is a second server, and said message from said prescribed location is sent from a web application programming interface running on said second server.

### Claim 3 (depends on 1)

The method of claim 1, wherein said second server is part of a cloud communications platform.

### Claim 4 (depends on 1)

The method of claim 1, wherein when said notification is not received by said server by said predetermined time, said processor further executes:
extracting information from said message of an originating telephone number provided with said telephone call, and identifying a device according to said extracted information;
determining whether said particular application or software is installed on said identified device;
when said particular application or software is installed on said identified device, transmitting a second message to said identified device via said particular application or software inquiring as to whether said identified device made said telephone call,
wherein said telephone call is verified as legitimate when an affirmative response to said second message is received from said identified device via said particular application or software.

### Claim 5 (depends on 4)

The method of claim 4, wherein when said particular application or software is not installed on said identified device, said processor executes a stored program analyzing whether said telephone call is legitimate.

### Claim 6 (depends on 1)

The method of claim 1, further comprising:
in response to determining that one of multiple concluding events has occurred in connection with said telephone call, transmitting a second instruction to said second telephone device to reactivate said call forwarding.

### Claim 7 (depends on 6)

The method of claim 6, wherein said multiple concluding events include:
said second telephone device hanging up on said telephone call after having picked up said telephone call, and
said telephone call being terminated by the originating party before being picked up by said second telephone device.

### Claim 8 (depends on 1)

The method of claim 1, wherein said server is configured to receive said notification from said first telephone device via a cloud messaging service.