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Title:
METHOD OF AND SYSTEM FOR LOCATING AN ARTICLE
Document Type and Number:
WIPO Patent Application WO/2007/060619
Kind Code:
A1
Abstract:
A method of locating an article which has an RFID tag operatively associated therewith includes storing on a database a plurality of unique RFID codes together with a description of the articles with which respective RFID codes are associated, and flagging an article stored on the database as errant in response to that article being reported as such. When a unique RFID code emitted from an RFID tag associated with an article, is received, the received RFID code is compared against at least the unique RFID codes of flagged articles stored on the database to determine if the RFID code is associated with an article flagged as errant. The location of the RFID tag is then obtained at least if the article was flagged as errant.

Inventors:
VISSER LOUWRENS (ZA)
PRETORIUS SAMUEL JACOBUS (ZA)
Application Number:
PCT/IB2006/054378
Publication Date:
May 31, 2007
Filing Date:
November 22, 2006
Export Citation:
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Assignee:
VISSER LOUWRENS (ZA)
PRETORIUS SAMUEL JACOBUS (ZA)
International Classes:
B60R25/00; G08B13/14
Foreign References:
DE10042805A12002-03-14
Attorney, Agent or Firm:
VAN DER WALT, Louis, Stephanus et al. (Adams & AdamsPlace 1140 Prospect Street, Hatfiel, PO Box 1014 0001 Pretoria, ZA)
Download PDF:
Claims:

CLAIMS:

1. A method of locating an errant article which has an RFID tag operatively associated therewith, which method includes: receiving by a monitoring device, when the RFID tag is proximate the monitoring device, a unique RFID code emitted from the RFID tag associated with the article; determining whether or not the proximate article is flagged in the monitoring device as errant; and raising an alert or sending an alert message in response to determining that the article is flagged as errant.

2. A method as claimed in claim 1 , which includes: receiving intermittently by the monitoring device a communication including a list of RFID codes associated with articles which are flagged as errant; and storing, at least temporarily, the list of RFID codes on the monitoring device.

3. A method as claimed in claim 2, in which determining whether or not the proximate article is flagged as errant includes comparing the unique RFID code received from the RFID tag associated with the proximate article against the stored list of RFID codes associated with articles which are flagged as errant, thereby to determine if the proximate article is flagged as errant.

4. A method as claimed in any of the preceding claims, which includes identifying the location of the monitoring device and sending the location with the alert message in response to determining that the proximate article is flagged as errant.

5. A method as claimed in claim 4, in which identifying the location of the monitoring device includes identifying a pre-defined location of the monitoring device if the monitoring device is fixed or determining the current location of the monitoring device using a geographical locator if the monitoring device is mobile.

6. A method as claimed in any of the preceding claims, in which sending an alert message includes sending by the monitoring device a communication including the

RFID code of the proximate article and an indication of the location of the monitoring device.

7. A method as claimed in any of the preceding claims, in which the RFID tag is attached to or integrated with the article.

8. A method of locating an article which has an RFID tag operatively associated therewith, which method includes storing on a database a plurality of unique RFID codes together with a description of the articles with which respective RFID codes are associated; flagging an article stored on the database as errant in response to that article being reported as such; receiving a unique RFID code emitted from an RFID tag associated with an article; comparing the received RFID code against at least the unique RFID codes of flagged articles stored on the database to determine if the RFID code is associated with an article flagged as errant; and obtaining the location of the RFID tag at least if the article was flagged as errant.

9. A method as claimed in claim 8, which includes from time to time updating the database with new RFID codes together with the description of the articles with which the respective RFID codes are associated.

10. A method as claimed in claim 8 or claim 9, which includes sending intermittently to a monitoring device configured to receive and identify RFID codes, a communication including a list of RFID codes associated with articles which are flagged as errant.

11. A method as claimed in claim 10, in which the monitoring device receives the unique RFID tag associated with an article, and in which the monitoring device compares the received RFID code against at least the unique RFID codes of flagged articles stored on the database to determine if the RFID code is associated with an article flagged as errant, the method including receiving from the monitoring device an alert message indicating that an RFID code of an article proximate to the monitoring

device which is flagged as errant, was received and then raising an alert in response to receipt of the alert message.

12. A method as claimed in claim 8 or claim 9, in which receiving a unique RFID code includes receiving from a monitoring device a communication including the RFID code of a proximate article; comparing the received RFID code includes interrogating the database to determine whether or not the proximate article is flagged as errant; and obtaining the location of the RFID tag includes receiving the location of the monitoring device from the monitoring device, the method further including raising an alert in response to determining that the proximate article is flagged as errant.

13. A monitoring device operable to locate an article which has an RFID tag operatively associated therewith, the monitoring device including: an RFID reader operable to receive, when the RFID tag is proximate the monitoring device, a unique RFID code emitted from the RFID tag associated with the article; and a geographic locator operable to determine the geographic location of the monitoring device thereby to determine the location of the proximate RFID tag.

14. A monitoring device as claimed in claim 13, which includes: a communication arrangement operable to receive a communication including a list of RFID codes associated with articles which are flagged as errant; and a memory module operable to store, at least temporarily, the list of RFID codes on the monitoring device.

15. A monitoring device as claimed in claim 14, which includes a comparator operable to compare the received RFID code from the proximate article against the stored list of RFID codes associated with articles which are flagged as errant, thereby to determine if the proximate article is flagged as errant.

16. A monitoring device as claimed in claim 15, which includes alert means operable to raise an alert or to send an alert message in response to determining that

the proximate article is flagged as errant.

17. A monitoring device as claimed in any of claims 14 to 16 inclusive, in which the communication arrangement is operable to send a communication including the unique RFID code of the proximate article and an indication of the location of the monitoring device.

18. A monitoring device as claimed in any of claims 14 to 17 inclusive, which is in the form of a cellular telephone.

19. A communications system operable to locate an article which has an RFID tag operatively associated therewith, which system includes: a database having stored thereon a plurality of unique RFID codes together with a description of the articles with which respective RFID codes are associated; flagging means operable to flag an article stored on the database as errant in response to that article being reported as such; and a communication arrangement to communicate with a monitoring device configured to receive and identify RFID codes.

20. A communications system as claimed in claim 19 in which the communication arrangement is operable to send intermittently to a monitoring device a communication including a list of RFID codes associated with articles which are flagged as errant.

21. A communications system as claimed in claim 20, in which the communication arrangement is operable to receive from a monitoring device an alert message which includes an indication of an RFID code of a proximate article which is flagged as errant, the system further including alert means operable to raise an alert in response to receipt of the alert message.

22. A communications system as claimed in claim 20, in which the communication arrangement is operable to receive from the monitoring device a communication including the unique RFID code of a proximate article and an indication of the location of the monitoring device, the system being operable to interrogate the

database to determine whether or not the proximate article is flagged as errant, the system further including alert means operable to generate an alert in response to determining that the proximate article is flagged as errant.

23. A monitoring system which includes: a plurality of monitoring devices as claimed in any of claims 13 to 18 inclusive; and a communication system as claimed in any of claims 19 to 22 inclusive.

Description:

METHOD OF AND SYSTEM FOR LOCATING AN ARTICLE

THIS INVENTION relates to a method of and a system for locating an article, particularly a movable or displaceable article.

The Applicants are aware of an RFID (radio frequency identification) tag which is attachable to an article and which can be interrogated by an RFID reader thereby to identify the article. The Applicants also believe that it is possible to integrate such a tag or functionality into an article.

According to one aspect of the invention, there is provided a method of locating an errant article which has an RFID tag operatively associated therewith, which method includes: receiving by a monitoring device, when the RFID tag is proximate the monitoring device, a unique RFID code emitted from the RFID tag associated with the article; determining whether or not the proximate article is flagged in the monitoring device as errant; and raising an alert or sending an alert message in response to determining that the article is flagged as errant.

It is to be appreciated that this method finds particular application in locating articles which have strayed, which have been stolen, which need to be tracked, or which need to be located for any other reason. Such articles are thus referred to as "errant" articles. By 'proximate' is meant that the RFID tag or transponder is within reading distance from the monitoring device. Also, the term "RFID tag" is intended to include any RFID functionality, whether a pre-manufactured tag attached to an article, or RFID functionality built into an article, e.g. an electronic article.

The method may include receiving intermittently by the monitoring device a communication including a list

of RFID codes associated with articles which are flagged as errant; and storing, at least temporarily, the list of RFID codes on the monitoring device.

Determining whether or not the proximate article is flagged as errant may include comparing the unique RFID code received from the RFID tag associated with the proximate article against the stored list of RFID codes associated with articles which are flagged as errant, thereby to determine if the proximate article is flagged as errant.

The method may further include identifying the location of the monitoring device and sending the location with the alert message in response to determining that the proximate article is flagged as errant.

Identifying the location of the monitoring device may include identifying a pre-defined location of the monitoring device if the monitoring device is fixed. This may include interrogating the database for the location of the monitoring device. Identifying the location of the monitoring device may instead include determining the current location of the monitoring device using a geographic locator if the monitoring device is mobile.

Sending an alert message may include sending by the monitoring device a communication including the RFID code of the proximate article and an indication of the location of the monitoring device.

Typically, the RFID tag is attached to or integrated with the article.

According to another aspect of the invention, there is provided a method of locating an article which has an RFID tag operatively associated therewith, which method includes storing on a database a plurality of unique RFID codes together with a description of the articles with which respective RFID codes are associated; flagging an article stored on the database as errant in response to that article being reported as such; receiving a unique RFID code emitted from an RFID tag associated with an article;

comparing the received RFID code against at least the unique RFID codes of flagged articles stored on the database to determine if the RFID code is associated with an article flagged as errant; and obtaining the location of the RFID tag at least if the article was flagged as errant.

Storing the RFID codes on a database may include the step of populating the database with the plurality of RFID codes together with a description of articles with which respective RFID codes are associated. Populating the database may also include entering data on monitoring devices, e.g. the location of fixed monitoring devices.

The method typically includes from time to time updating the database with new RFID codes together with the description of the articles with which the respective RFID codes are associated.

In one embodiment of the invention, the method includes sending intermittently to a monitoring device configured to receive and identify RFID codes, a communication including a list of RFID codes associated with articles which are flagged as errant. In such a case, the monitoring device may receive the unique RFID tag associated with an article, and the monitoring device may compare the received RFID code against at least the unique RFID codes of flagged articles stored on the portion of the database received by the monitoring device to determine if the RFID code is associated with an article flagged as errant. The method may then include receiving from the monitoring device an alert message indicating that an RFID code of an article proximate to the monitoring device which is flagged as errant, was received and then raising an alert in response to receipt of the alert message.

Receiving a unique RFID code may include receiving from a monitoring device a communication including the RFID code of a proximate article. Comparing the received RFID code may include interrogating the database to determine whether or not the proximate article is flagged as errant. Obtaining the location of the RFID tag may include receiving the location of the monitoring device from the monitoring device, or receiving information on the identity of a fixed monitoring device. The method may further include raising an alert in response to determining that the proximate article is

flagged as errant.

The step of comparing the received RFID code against the plurality of unique RFID codes stored on the database may thus take place at the monitoring device or at a remote location hosting the database.

The alert may be raised remotely from the monitoring device, for example at a computer which hosts the database, or at any other computer, server or terminal in communication therewith. The alert may therefore be communicated to interested third parties, for example, the police, assurance companies, parties specifically created to monitor errant articles, or the like.

When an article is recovered or no longer needs to be located, the flag may be removed so that the article is no longer flagged as errant.

It will be appreciated that the RFID tag may be permanently attached or removably attached to the article. The RFID tag may be incorporated in the article such as in the circuitry of the article, moulded into the article, made an integral part of the article, or the like. This may be advantageous if the article is a cell phone, a motor vehicle, a goods container, or the like. The method may therefore include the prior step of attaching the RFID tag to the article.

According to a further aspect of the invention, there is provided a monitoring device operable to locate an article which has an RFID tag operatively associated therewith, the monitoring device including: an RFID reader operable to receive, when the RFID tag is proximate the monitoring device, a unique RFID code emitted from the RFID tag associated with the article; and a geographic locator operable to determine the geographic location of the monitoring device thereby to determine the location of the proximate RFID tag.

The monitoring device may include a communication arrangement operable to receive a communication including a list of RFID codes associated with articles which are flagged as errant; and

a memory module operable to store, at least temporarily, the list of RFID codes on the monitoring device. The memory module may be in the form of a RAM (random access memory) module.

The monitoring device may also include a comparator operable to compare the received RFID code from the proximate article against the stored list of RFID codes associated with articles which are flagged as errant, thereby to determine if the proximate article is flagged as errant. The monitoring device may include an electronic processor programmed to act as a comparator. The processor may be in the form of a CPU (central processing unit).

The monitoring device may further include alert means operable to raise an alert or to send (e.g. using the communication arrangement) an alert message in response to determining that the proximate article is flagged as errant. The alert means may be in the form of, for example, a loudspeaker, thereby to provide an audible indication. Instead, or in addition, the alert means may be in the form of a visual or tactile indicator, for example a display screen or a vibrator.

Typically, the communication arrangement is operable to send a communication including the unique RFID code of the proximate article and an indication of the location or the identity of the monitoring device.

The monitoring device may be fixed or mobile. If the monitoring device is fixed, its geographic location may be pre-determined and may further be stored on the database.

A fixed monitoring device may be powered by a battery or may have connection means for connection to a supply of electricity. A fixed monitoring device may be installed where tagged articles are, at least temporarily, likely to be proximate and/or stationary, for example, at petrol stations, toll gates, border posts, shopping centres, traffic lights, residential areas, and the like. The monitoring device may be hidden from plain sight or may take the form of an innocuous item, for example, a pot plant or a door frame.

The geographic locator may be in the form of a GPS (global positioning system) unit, a GSM modem using triangulation, or the like. A mobile monitoring device may be in the form of a handheld device, for example a cellular telephone or a whstwatch. A mobile monitoring device may be powered by a battery, for example, a rechargeable battery.

In one embodiment if the invention, the monitoring device is in the form of a cellular telephone. The invention thus extends to a cellular telephone having an RFID reader operatively connected thereto or operatively integrated therewith. The invention further extends to a computer program executable on a cellular telephone to direct the operation of the RFID reader.

The RFID tag may be passive, not having an internal power source and therefore not actively transmitting the unique RFID code. The RFID reader may be an RFID transponder or interrogator which is configured to broadcast intermittently an interrogating signal. If a passive RFID tag is within range of the interrogating signal, the RFID tag may be energised by the interrogating signal and transmit its RFID code in response thereto. The interrogating signal may be broadcast, for example, every 30 seconds.

Instead, or in addition, the RFID tag may have an internal power source and may intermittently broadcast its RFID code for reception by any monitoring device which is within range.

According to yet another aspect of the invention, there is provided a communications system operable to locate an article which has an RFID tag operatively associated therewith, which system includes: a database having stored thereon a plurality of unique RFID codes together with a description of the articles with which respective RFID codes are associated; flagging means operable to flag an article stored on the database as errant in response to that article being reported as such; and a communication arrangement to communicate with a monitoring device configured to receive and identify RFID codes.

The database may be hosted by a computer. The computer may be programmed to flag an article as errant in response to that article being reported as such.

The communication arrangement may be operable to send intermittently to a monitoring device a communication including a list of RFID codes associated with articles which are flagged as errant.

The communication arrangement may also be operable to receive from a monitoring device an alert message which includes an indication of an RFID code of a proximate article which is flagged as errant, the system further including alert means operable to raise an alert in response to receipt of the alert message.

The communication arrangement may further be operable to receive from the monitoring device a communication including the unique RFID code of a proximate article and an indication of the location or the identity of the monitoring device, the system being operable to interrogate the database to determine whether or not the proximate article is flagged as errant, the system further including alert means operable to generate an alert in response to determining that the proximate article is flagged as errant.

The communication arrangement may be in the form of: a RF (radio frequency) receiver and/or transmitter operable to communicate with each of the monitoring devices for direct RF communication; a GSM (global system for mobile communications) modem operable to communicate with each of the monitoring devices for communication across a cellular telephone network; a satellite receiver and/or transmitter operable to communicate with each of the monitoring devices for communication via a satellite; an Internet connection operable to communicate with each of the monitoring devices for communication via the Internet; or a combination of the above.

According to yet a further aspect of the invention, there is provided a

monitoring system which includes a plurality of monitoring devices as hereinbefore described and a communication system as hereinbefore described.

Preferably, the monitoring devices are geographically spaced.

Further features of the invention will become apparent from the following description, by way of non-limiting example, with reference to the accompanying diagrammatic drawings.

In the Figures:

Figure 1 is a schematic block diagram of a system for locating an article which has an RFID tag operatively attached thereto or integrated therewith, in accordance with the invention;

Figure 2 is a more detailed block diagram of a mobile monitoring device of the system in Figure 1 ; and

Figure 3 is a flow diagram of the steps of the method in accordance with the invention.

Referring to Figure 1 of the drawings, reference numeral 10 generally indicates a system, in accordance with the invention, for locating an article. A computer 12 hosts a database 14, and the operation of the computer 12 and the database 14 is directed by a computer program, schematically indicated by reference numeral 16.

The computer 12 has a communication arrangement or communication means 18 operatively connected thereto for communication via a telecommunication network 20. In the example shown in Figure 2, the communication means 18 is a GSM modem, and the telecommunication network 20 is therefore a cellular telephone network.

A plurality of monitoring devices 22.1 ...22. n (see Figure 2 for more detail) also have a communication arrangement or communication means operatively connected thereto for communication with the computer 12, and hence the database 16, across the cellular telephone network 20. The monitoring devices 22.1 ...22.n can be fixed or mobile, but in this example they are mobile. The monitoring devices 22.1 ...22. n

can take the form of a dedicated electronic device, or can be integrated into existing devices, for example, cellular telephones, whstwatches, motor vehicles, and the like. The monitoring devices 22.1...22. n are geographically spaced from one another thereby to provide a country wide network of monitoring devices 22.1 ...22.n. The monitoring devices 22.1...22. n can be carried by the general public and/or dedicated personnel.

A plurality of articles 26.1...26.n has passive RFID tags 28.1...28.n attached thereto. The RFID tags 28.1...28.n can be integrally attached to the article

26.1...26.n during manufacture of the article 26.1...26.n, or can be retrofitted, either permanently or removably. Any article 26.1...26.n which may at some stage need to be located could be fitted with an RFID tag 28.1...28.n, as well as containers of articles.

Each RFID tag 28.1...28.n has a unique RFID code (conceptually indicated by reference numeral 30.1...30.n) associated therewith, and the unique RFID code 30.1...30.n is therefore also associated with the article 26.1...26.n to which the RFID tag 28.1...28.n is attached.

Figure 2 shows a more detailed block diagram of a monitoring device 22.1 , which in this example is integrated with a cellular telephone. The cellular telephone 22.1 has an RFID reader or interrogator 40 operatively connected thereto. The RFID interrogator 40 is operable to interrogate and energise any proximate RFID tags 28.1...28.n, and to receive the RFID code 30.1...30.n broadcast from an interrogated RFID tag 28.1...28.n. The cellular telephone 22.1 has operatively connected thereto a storage unit or memory module 42 and a processor 44. The storage unit 42 and the processor 44 could be pre-existing components provided by the proprietor of the cellular telephone 22.1. The processor 44, together with a computer program loaded thereon, directs the operation of the cellular telephone 22.1 in as far as it relates to this invention. The cellular telephone 22.1 also has a geographic locator 46, in the form of a GPS unit, operatively connected thereto. In another embodiment, the cellular phone 22.1 could be located using thangulation. The cellular phone 22.1 has display means 48 in the form of an LCD (liquid crystal display) or TFT (thin film transistor) screen. Advantageously, the monitoring devices 22.1 ...22.n could also be integrated into motor vehicles thereby to provide effective roaming of the monitoring devices 22.1...22. n.

Figure 3 is a flow diagram 100 of the steps of the method, and is described in combination with Figures 1 and 2.

In use, and referring now to Figures 1 , 2, and 3, the database 14 has stored thereon a list of RFID codes 30.1...30.n together with their associated articles 26.1...26.n. If an owner (or other interested party) reports an article 26.1...26.n as errant, the database 14, under the direction of the computer program 16, flags the article as errant, at block 102 of the flow diagram 100. Thus a processor (not shown) on which the computer programme is executed functions as flagging means. A list of errant articles is periodically communicated to the monitoring devices 22.1 ...22.n, for example every hour, via the cellular network 20, at block 104. The list of errant articles is stored in the storage units 42 of the monitoring devices 22.1...22.n.

In this example, an article 26.2 has been stolen, and therefore reported by its owner as errant. The article 26.2 on the database 14 is flagged accordingly, at block 102. The list of errant articles is communicated to all the monitoring devices 22.1 ...22.n, at block 104, and each monitoring device 22.1 ...22.n stores that list in its storage unit 42.

The monitoring devices 22.1 ...22. n are configured to broadcast from their RFID interrogator 40 an interrogating signal every 30 seconds, at block 106. The monitoring devices 22.1 ...22.n wait for a response, at block 108. If no RFID tag is proximate a monitoring device 22.1 ...22.n, there will be no response, at branch 108.1. The monitoring devices 22.1...22. n then repeat the process from block 106.

If article 26.1 (not flagged as errant) moves into proximity to a monitoring device 22.1 ...22.n (or vice versa), the interrogating broadcast from the monitoring device 22.1...22.n energises the RFID tag 28.1 , in response to which the RFID tag 28.1 broadcasts its RFID code 30.1 , at branch 108.2. The RFID interrogator 40 in the monitoring device receives the broadcast RFID code 30.1 , at block 110, and the processor 44 compares the received RFID code 30.1 with the list of RFID codes associated with errant articles stored in the storage unit 42, at block 112. The processor 44 thus acts as a comparator. In this example, article 26.1 has not been

reported as errant, and therefore does not occur on the list of errant articles, at branch 112.1. The monitoring device 22.1 ...22.n takes no further action and disregards the received RFID code 30.1 , at block 114, although if desired a log file can be kept of received RFID codes 30.1 ...30. n and the location(s) of the monitoring device when said RFID codes 30.1...3O.n are received.

If, instead, article 26.2 (the errant article) moves into proximity to a monitoring device 22.1...22.n, the monitoring device 22.1 ...22.n receives the RFID code 30.2, at block 110, in the same fashion as above described, and compares the RFID code 30.2 with the list of RFID codes associated with errant articles, at block 112. The RFID code 30.2 appears on the list, at branch 112.2, and the proximate monitoring device 22.1...22.n raises an alert, at block 116. The alert could be by way of a sound or vibration, but preferably is by way of a message displayed on the display means 48 of the monitoring device 22.1...22. n. The display means 48 thus functions as alert means. The message includes a description of the errant article 30.2, so that the operator of the proximate monitoring device 22.1 ...22. n can easily identify the errant article 30.2.

Additionally, and under the direction of the processor 44, the monitoring device 22.1 ...22.n determines its location using the GPS unit 46 connected thereto, at block 118. The proximate monitoring device 22.1 ...22.n then communicates an alert together with the received RFID code 30.2 of the errant article and the location of the proximate monitoring device 22.1 ...22. n to the computer 12, at block 120. An operator of the computer 12 will be alerted that an errant article 30.2 has been located. The computer 12 can be configured to communicate the alert, for example over the Internet, to other interested parties, for example, the owner of the errant article 30.2, the police, and so forth, at block 122.

It is however to be appreciated that an alert does not necessarily have to be communicated to a person controlling the monitoring device. It may in fact be dangerous under certain circumstances if an alert is communicated to said person. The monitoring device may thus be set up or configured only to communicate an alert to a remote computer or a remote operator.

Once the errant article 26.2 is recovered or no longer needs to be tracked,

the owner reports the change of status of the article 26.2, and the flag is removed so that the article 26.2 is no longer flagged as errant. The method of the flow diagram 100 is repeated periodically.

The inventor believes that the invention as exemplified has a number of advantages.

First, the monitoring devices can be integrated with relative ease into the circuitry of a motor vehicle, in which case the contents of the vehicle and its surroundings will be checked periodically. Also, a cellular telephone can conveniently be adapted to function as a monitoring device as cellular telephones typically have at least some of the components of the monitoring device already present. Depending on the specifications of the particular cellular telephone, the monitoring device could use the telephone's CPU, power supply, GPS capability, and data transmission capabilities.

Secondly, because of the relative ease of creating the monitoring devices, a wide network of monitoring devices can be established to provide coverage across a large area.

Thirdly, the system can provide for inconspicuous and unobtrusive monitoring of articles. In future, it would be advantageous for all articles of value to be equipped with RFID tags uniquely identifying those articles. Such RFID tags can be attached to or integrated with the articles. Such attachment or integration may be made by the owners of the articles, insurance companies insuring the goods, asset tracking and recovery companies, or the manufacturers of the articles themselves.