Comsat Corporation v Telstra Corporation Limited

[2001] APO 19

OFFICIAL NOTICE

DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS

Application  :          No. 684305 in the name of Comsat Corporation

Title:          Secure Communication System

Action: Opposition under Section 59 of the Patents Act 1990 by Telstra Corporation Limited.

Decision:          Issued            .

Abstract

The claims defining the invention were found not to be fairly based because they did not adequately define the conversion of secure voiceband data for transmission over a digital communication channel. This feature being plainly essential to the inventive concept.

The invention defined by claims 8, 9 and 10 was also found to lack an inventive step, however there was insufficient evidence to show that the invention defined by other claims was obvious.

Given the change to the opponent's case that became apparent only at the hearing there was no award of costs.

PATENTS ACT 1990

DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS

Re:Patent Application No. 684305 by Comsat Corporation and opposition under Section 59 of the Patents Act 1990 by Telstra Corporation Limited.

BACKGROUND

Comsat Corporation (Comsat) filed the present application on 10 May 1994 as an international application PCT/US94/04976 designating Australia. It claims priority from US application 065,017 filed on 24 May 1993.

On 11 December 1997 the application was advertised accepted and Telstra Corporation Limited (Telstra) filed its notice of opposition on 11 March 1998. The evidentiary stages were completed on 7 July 2000 and the matter came to hearing in Sydney on 14 February 2001. Comsat was represented by Mr C O'Sullivan, patent attorney of FB Rice & Co, Sydney who was assisted by Ms T Webb also of that firm. Telstra was represented by Mr D Yates of counsel who was instructed by Mr R Miller of Spruson & Ferguson, Sydney.

GROUNDS OF OPPOSITION

At the hearing Mr Yates indicated that Telstra would essentially confine its opposition to the ground that the invention claimed lacks an inventive step over what is admitted or acknowledged as known on the face of the specification and/or in light of the publication "Transmission of Group 3 Facsimile over Inmarsat Maritime Digital Satellite Mobile Channels", International Journal of Satellite Communications, Vol. 10, 177-182 (1992), Dimolitsas et al. It was also asserted that claim 8 and dependant claims were not fairly based because they fail to define the essential feature of distinguishing between secure and unsecure data. As such much of the considerable documentary evidence filed in this matter was not relied on.

SPECIFICATION

The field of the invention is said to be the direct interfacing of secure communication services, particularly the US government's Secure Terminal Unit III (STU-III), over low-rate digital mobile systems. Low rate in this context appears to mean low encoding rates which are used in digital mobile voice communications systems, and particularly satellite systems, to allow speech to be transmitted over narrower bandwidths and hence to achieve higher subscriber capacity. It is said that "the digitisation of mobile networks has made the transparent support of non-voice traffic impossible without the development of specialised interworking functions, which are tailored to specific end-user applications".

The general object of the invention is then stated as being to provide a system for supporting a secure system over a digital system and, as a further object, to provide a system for supporting STU-III over low rate digital systems including mobile systems. Following this there is a consistory statement essentially equivalent to the independent claims. On page 2C it becomes apparent that the functionality achieved by the invention can be described by means of a Secure Interface Unit (SIU) architecture and a Secure Communications (SC) protocol. Subsequently the primary function of the SIU architecture is given as "the demodulation of secure traffic in the secure terminal-satellite direction and the re-modulation in the mobile or fixed station-secure terminal direction". Apart from secure modems the SIU is said to incorporate "a rate adaptation and protocol packetisation mechanism, a channel encoding process, an elastic buffer and an echo canceller". The SC protocol is said to be based on a packetised structure that interfaces with the voice channel to provide a secure-to-clear and clear to secure communication in a seamless manner. It also provides for controlled and synchronised call establishment on an end to end basis.

There are 40 claims, 5 of which are independent.  Claims 1 and 8 reads as follows:

"1.       A communication system comprising:
a first secure communication terminal for providing secure analog voiceband data;

a first processing circuit connected to receive the analog voiceband data from the first secure communication terminal and for converting the received analog voiceband data into secure baseband data, said first processing circuit transmitting the baseband data;

a second processing circuit connected to receive the transmitted baseband data from the first processing circuit, and for converting the received baseband data into analog voiceband data;

a second secure communication terminal for receiving the analog voiceband data from said second processing circuit; and

a telephone unit for providing non-secure data signals, wherein the first processing circuit includes a signal detector for distinguishing between secure data signals received from said first secure communication terminal and non-secure data signals received from said telephone unit."

"8.       A communication system, comprising:
           a first secure communication terminal for providing analog voiceband data;
           a first processing circuit connected to receive the analog voiceband data from the first secure communication terminal and for converting the received analog voiceband data into secure baseband data, said first processing circuit transmitting the secure baseband data;
           a second processing circuit connected to receive the transmitted secure baseband data from the first processing circuit, and for converting the received secure baseband data into analog voiceband data;
           a second secure communication terminal for receiving the analog voiceband data from said second processing circuit; and
           a satellite communication link;
           wherein said secure baseband data is transmitted from said first processing circuit via said satellite communication link, and wherein at least one of said first and second secure communications terminals is an STU-III terminal."

To form a better understanding of the invention it is important to recognise that the standard STU-III terminal is capable only of analog output, either POT (Plain Old Telephone) in unsecure mode or, typically, V.26 or V.32 modem line signals in secure mode (a digital version, ie STU-III D, exists but this is not relevant to the present application). Normally the terminal is used in POT mode to establish a non-secure call. The parties then insert their respective smart key (Crypto Ignition Key) to switch to secure mode allowing transmission of encrypted voice or data signals including fax. Alternatively a call may be made or automatically received in secure mode.

As will be apparent, the standard STU-III was designed to function over analog lines and can operate over analog voiceband radio networks. However, digital voiceband networks are generally optimised for speech and given the reduce coding rates mentioned in the specification it is apparent that transmission of the secure modulated data signal will not be effective on digital systems. Therefore to use a standard STU-III over a digital network requires a special interface to demodulate the voiceband data signal and code the data stream for effective use of the particular digital data channel involved. This then is the context for the present invention.

DECISION

Before turning to the primary question of whether the invention claimed involves an inventive step, I will look at the issues raised in relation to fair basis. In this regard I am guided by the well known decision in The Mullard Radio Valve Co. Ld. v Philco Radio and Television Corp. of Great Britain Ld., (1936) 53 RPC 323 where it was said that:

"The consideration which the patentee gives to the public disclosing his inventive idea entitles him in return to protection for an article which embodies his inventive idea but not for an article which, while capable of being used to carry his inventive idea into effect, is described in terms which cover things quite unrelated to his inventive idea, and which do not embody it at all."

and

"A patentee is granted his monopoly in order to protect the invention which in his specification he has communicated to the public. He is not entitled to claim a monopoly more extensive than is necessary to protect that which he has himself said is his invention ... If an inventor claims an article as his invention, but the article will only achieve his avowed object in a particular juxtaposition and his inventive idea consists in the discovery that in that particular juxtaposition it will give new and useful results, I do not think that he is entitled to claim the article at large apart from the juxtaposition which is essential to the achievement of those results."

Telstra argue that the feature of discrimination between secure and non-secure traffic is essential to the invention described but that this feature is not defined in claim 8 and dependant claims. In this regard I note that the discrimination feature is certainly predominate in the description of the embodiments and in a number of independent claims. On the other hand the broad object of the invention is merely a system "for supporting a secure system over a digital system" and I find that a system for achieving that is disclosed. On this interpretation, discrimination can be seen as a preferable feature to achieve the secondary object of supporting STU-III over low rate digital systems since it is necessary for compatibility with normal STU-III operation modes. Consequently I do not agree that discrimination between secure and non-secure signals is an essential feature of the invention as described in the specification read as a whole.

However, since the whole basis for the inventive concept appears to be to facilitate the use of a secure terminal producing modulated voiceband data over a digital network, the claims can equally be criticised because they go well beyond this. For example a number of the claims refer only to producing and transmitting "baseband data" or "a secure interface unit for transmitting/ receiving secure telephone signals" and this, on its plain meaning, includes the possibility of analog baseband data transmitted on an analog communication network. Those claims, for example claim 24, that refer to using a voice codec for transmitting or receiving telephone signals may to some extent imply a digital transmission system for the non-secure component but since the crux of the invention is the conversion and digital transmission of secure voiceband, and this feature is absent, they still stray too far from the inventive concept disclosed.

I note from Mr O'Sullivan's summary of submissions that Comsat consider the invention described to be "a system for supporting the direct interfacing of secure communication services" and that "The invention preferably concerns transmission over a digital system and more preferably a satellite system". In my view such a broad interpretation of the inventive concept finds no support in the specification and for the reasons already given I find the claims not to be fairly based on the matter described.

I will turn now to the question of whether what is claimed involves an inventive step. Telstra have asserted lack of an inventive step on the basis that the invention is obvious on the face of the specification and/or in light of the publication "Transmission of Group 3 Facsimile over Inmarsat Maritime Digital Satellite Mobile Channels", International Journal of Satellite Communications, Vol. 10, 177-182 (1992), Dimolitsas et al. This approach seeks to rely on the decision of the High Court in NV Philips Gloeilampenfabrieken v Mirabella International Pty Ltd (1995) 183 CLR 655 which established that the threshold requirement for patentability is not met if "it is apparent on the face of the specification that the quality of inventiveness necessary for there to be a proper subject of letters patent under the Statute of Monopolies is absent".

Futhermore in Bristol-Myers Squibb Co v F H Faulding & Co Ltd [2000] FCA 316 Black, CJ and Lehane J considered the decision of the High Court and indicated that (with my underlining):

"In our view, in the light of the authorities to which we have referred, Philips stands for the proposition (as a matter of construction of the 1990 Act) that if, on the basis of what was known, as revealed on the face of the specification, the invention claimed was obvious or did not involve an inventive step - that is, would be obvious to the hypothetical non-inventive and unimaginative skilled worker in the field (Minnesota at 260 per Barwick CJ) - then the threshold requirement of inventiveness is not met. Some elaboration, however, is required in relation to what the specification reveals as "known". If a patent application, lodged in Australia, refers to information derived from a number of prior publications referred to in the specification or, generally, to matters which are known, in our view the Court - or the Commissioner - would ordinarily proceed upon the basis that the knowledge thus described is, in the language of s 7(2) of the 1990 Act, part of "the common general knowledge as it existed in the patent area". In other words, what is disclosed in such terms may be taken as an admission to that effect. In substance, we think, that is what happened, both in Microcell and in Philips. If, however, the body of prior knowledge disclosed by the specification is insufficient to deprive what is claimed of the quality of inventiveness, then the only additional knowledge or information which will be taken into account is knowledge or information of a kind described in s 7(2) of the 1990 Act. That again, in our view, is consistent with the approach taken in Microcell. It is also, with respect, the only approach which does not, in practical terms, render s 18(1)(b)(ii) otiose. Of course, once that additional knowledge is taken into account, one is applying s 18(1)(b)(ii), not the opening words of s 18(1) - unless, perhaps, one might apply either, there being, in this respect, no difference between them."

In relation to the present specification there are a number of matters which I believe the specification is asserting to be known and from the above principles can be considered, part of "the common general knowledge as it existed in the patent area". These include notably:

• The U.S. Governments Secure Terminal Unit-III (STU-III);

• The Future Secure Voice System (FSVS) Signalling Plan FSVS-210, Revision F, 31 March 1992;

• The FSVS Terminal Performance Specification FSVS-220, Revision B, 26 February 1988;

• The Inmarsat-M SDM; and

• The CCITT Recommendation T.30 protocol as described in CCITT Recommendation V.32, "Procedures for Document Facsimile Transmission in the General Switched Telephone Network", Blue Book, Melbourne, November 1988.

While the specification does not refer to this information using language such as "known", the specification refers to some as being included by reference and the clear implication is that the reader is assumed to be aware of all these matters and would understand their relevance to the invention described. There is of course a suggestion in Telstra's evidence that at least the FSVS documents were restricted and not available in Australia at the priority date but Professor Lebow provides evidence suggesting the contrary. Even if Professor Lebow is confusing availability in the US or Canada with availability in Australia, Mr Williams says "the level of knowledge of a hypothetical telecommunication engineer living in the USA in 1993 would be no different from one living in Australia". Consequently in my view Comsat through its own evidence has conceded that the documents were available to the public in Australia and, having been acknowledged in the specification, they can be considered as common general knowledge for the purpose of assessing inventiveness.

Telstra argue that the invention claimed lacks an inventive step on the face of the information referred to in the specification because, inter alia, the invention operates in modes compatible with the standards or protocols referred to and, in particular, relies on communication type discrimination based on the normal control tones associated with those standards.

To establish lack of an inventive step an opponent is required to establish on the balance of probabilities that the invention would have been obvious to a non-inventive worker in the field, equipped with the common general knowledge in that particular field as at the priority date. In Wellcome Foundation Ltd v V R Laboratories (Aust) Pty Ltd (1981) 148 CLR 262, Aickin J indicated (at 286) that:

"The test is whether the hypothetical addressee faced with the same problem would have taken as a matter of routine whatever steps might have led from the prior art to the invention, whether they be the steps of the inventor or not."

In relation to what would characterise a skilled addressee in the art, I notice some disagreement among the expert witnesses. Mr Hart, who is an Australian consulting engineer, says in his opinion "the addressee of the specification would be a telecommunications engineer, and in particular someone involved in the area of satellite telecommunications". The declarants for the applicant, including Professor Lebow and Mr Williams, on the other hand appear to indicate that  the field of the invention is in secure or military telecommunications and allege that misconceptions arise in the evidence-in-support because Telstra's declarants including Mr Hart are commercial telecommunications experts.

On the face of the specification I believe that "secure" certainly does have a specific meaning and would include at least encryption. Therefore I find that the field of the invention is in secure telecommunications but not solely satellite communications since the scope of the specification goes beyond this. It should also be apparent that "secure" does not limit the field to military or defence applications but would also include commercial applications where security is important. Hence I equate the hypothetical skilled addressee to be a non-inventive graduate telecommunications engineer with knowledge of secure systems in either a commercial or defence environment (Lucent Technologies Inc v Krone Aktiengesellschaft (No 3) [2000] FCA 100).

In taking a problem-solution approach to the question of obviousness it is established that the problem addressed can be "inferred on the basis of the specification as a whole and the surrounding facts" (Monsanto Company v Zeneca Ltd 36 IPR 120). Putting aside the fair basis issue discussed previously and reading the claims to limit the invention to communication over digital systems, the problem generally addressed appears to be how to facilitate the use of a secure terminal producing modulated voiceband data over a narrow band digital system. Assuming under the principle of Philips that the information elements listed above were part of common general knowledge, the question then would be whether the skilled addressee in possession of that knowledge would take as a matter of routine the steps leading from the prior art to the invention claimed. In seeking to answer this question I must say that the evidence provided by the parties is not overly helpful particularly given the footing on which Telstra now wishes to put its opposition. Nevertheless I find particularly within Mr Hart's declaration some rudimentary indication of what would be known to the skilled addressee in Australia even though in general both he and Mr Percival appear over qualified and for that reason I consider their evidence with some caution.

On the information before me I do not believe it is unreasonable to expect that the skilled addressee would have, at least, recognised the problem associated with attempting to send voiceband data over a narrowband digital channel and would consequently recognise that the voiceband data needed to be converted to baseband data before transmission on the digital channel. It is after all based on the simple recognition that that the maximum bit rate available while adequate for voice will be unable to render voiceband data at the rate required by the voiceband modem. As such I believe the skilled addressee would have directly arrived at the invention defined in claims 8, 9 and 10 which does not involve non-secure telephone signals and merely refers to conversion to baseband data, use of STU-III devices and transmission on satellite communication links. Comsat points out that the secure nature of the communications adds complexity to the system but this simply is not reflected in the claims. Secure voiceband data is essentially no different to other voiceband data and if there is complexity it is said to be in switching between secure and non-secure modes. The claimed invention does not require this and is not implied merely by requiring one or both of the secure terminals to be a STU-III.

In relation to the other claims I believe it is necessary to reconsider what is the problem addressed by the invention so defined and clearly it is how to facilitate the use over a digital channel of a secure system producing modulated voiceband data in secure mode and analog voice signals in clear mode. That is, in terms of the secondary object stated on page 2 of the specification, how can the STU-III be used compatibly over a digital link? While it may be easy to say that tone detection was a common technique in discriminating call types or that a STU-III may produce detectable tones when switching modes, it is a significant leap to say, without the benefit of hindsight, that the addressee would as a matter of routine combine selected elements of common general knowledge to arrive at a system requiring discrimination between secure and unsecure voiceband signals as claimed. Remembering that we are concerned with a non-inventive addressee I do not find anything on the face of the specification that would provide a clear inducement to try such a configuration over other alternatives and there is insufficient expert evidence otherwise to indicate that the solution claimed would readily occur to the addressee on the basis of other elements of common general knowledge. On the contrary the evidence suggests that others have grappled with the same problem but have not apparently arrived at the same solution.

Telstra's argument however does not end there. They also point to the Dimolitsas paper which they assert is prior art information that may be considered by virtue of sub-section 7(3)(a). Indeed this document was apparently available in the library of the University of New South Wales before the priority date of the present application and I believe there is a reasonable expectation that the skilled addressee would have ascertained, understood and regarded it as relevant to work in the relevant field. In particular the document deals with a key aspect of the present problem, that is, how to operate standard devices producing voiceband data over a narrowband digital link. The paper itself relates to the interworking of "off the shelf" group 3 facsimile terminals over Inmarsat-B, which is a maritime digital communication system. The terminals in that case are said to produce 9.6 kb/s voiceband data which would "normally require the allocation of a transmission rate of at least 40 kb/s when transported over digital links." Since the digital channel capacity in Inmarsat-B does not exceed 10.5 kb/s an interworking solution is suggested which provides for the reduction in bandwidth as well as the conversion of facsimile protocols and includes conversion of voiceband data to baseband.

The similarity of figure 1 in the paper to figure 1 of the patent specification was pointed out to me. It shows a POT and a facsimile terminal connected via PSTN to a Coast Earth Station CES which includes a Facilities Assignment Processor (FAP) with outputs to a Digital Voice Codec and a Facsimile Interface Unit (FIU) which similarly connect to RF side of the earth station. The Ship Earth Station (SES) shows the reverse although without the FAP as in figure 1 of the present application.

If there is any doubt I believe this publication together with the acknowledged common general knowledge clearly indicates that the invention defined in claims 8 to 10 lacks an inventive step. In relation to the other claims however the Dimolitsas paper gives virtually no indication of how the FAP works and what is does say is that:

"For ship originated facsimile calls, the SES establishes a circuit in the facsimile data mode on the basis of a requested PSTN service address. For PSTN originated automatic facsimile calls, the SES establishes a circuit in the facsimile mode on the basis of the mobile service address dialled (a separate number is assigned to the SES FTE). Finally, in the manually established mode the call is established initially as a voice call. Subsequently, the SES recognizes the 2100Hz/1100Hz facsimile call set up tones and an out-of-band request to convert the voice circuit to a data circuit is generated."

Hence, while there is mention of tone recognition, it not used in the same way as in the present invention. Calls from the PSTN are not discriminated within the FAP on the basis of set up tones or other signal detection but the primary discrimination appears to be on the basis of the number assigned. That is, there are separate telephone numbers for voice and facsimile transmission to the SES. When tone discrimination is used in manual mode it is the SES which responds not the FAP and the change of circuits is made by an out-of-band request.

Consequently, even if a skilled addressee would see this as a partial solution to the problem it does not seem to advance Telstra's case in relation to the discrimination between secure and non-secure data signals, for the reasons indicated above. The disclosure may in fact be a teaching away from the claimed solution but there is simply too little specific expert evidence for me to reach a conclusion either way.

CONCLUSION

I find that the invention claimed is not fairly based on the matter described in the specification. While the feature of discrimination between secure and non-secure data signals is not considered to be essential to the invention disclosed, the conversion of secure voiceband data for transmission on a digital channel certainly appears to be. As this feature is not adequately defined in the claims they lack fair basis.

It is clear that claims 8, 9 and 10 lack an inventive step either on the face of the specification or in light of the Dimolitsas paper. However the evidence is insufficient for me to find that the invention claimed in others of the claims is obvious.

Consequently I find that the opposition has been made out in part and allow the applicant sixty days from the date of this decision in which to file amendments that overcome the deficiencies I have identified above.

COSTS

Telstra has been partially successful in its opposition but in considering the award of costs I am mindful of the significant change in the opponent's case that became apparent only at the hearing. The applicant was required to prepare its case on the basis of a considerable volume of evidence that was not ultimately relied on and in the circumstances I believe it is appropriate to make no award of costs.

Philip Spann
Delegate of the Commissioner of Patents

Patent attorneys for the applicant  :  F B Rice & Co, Balmain

Patent attorneys for the opponent   :  Spruson & Ferguson, Sydney