Airsense Technology Limited v Vision Systems Limited

OFFICIAL NOTICE
DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS
Application : No. 689484 in the name of AIRSENSE TECHNOLOGY LIMITED

Title: Smoke Detection System

Action: Opposition under Section 59 of the Patents Act by VISION SYSTEMS LIMITED

Decision: Issued 2 March 2004 .
Abstract

The invention relates to the detection of the content of impurities in a gaseous medium. The invention has particular application for the detection of smoke from a fire.
The opponent asserted the applicant was not entitled to the invention as employees of the applicant had previously worked for a predecessor subsidiary of the opponent and had obtained the invention from the opponent.
It was found that the applicant is not disqualified from entitlement to the invention by way of association of its staff with the predecessor subsidiary of the opponent.
The opponent also asserted the claimed invention was not novel and did not have an inventive step.
It was found the invention as claimed in claims 1 and 3 does not have an inventive step.
Additionally there is a problem with the fair basis and clarity, and consequent entitlement to the claimed priority date, of one of the dependent claims. An amendment to bring the description of the invention in line with the claim would not remedy the situation. The claim is clearly flawed.
It was found there is patentable subject matter in the specification. The applicant was given an opportunity to amend the claims to define that subject matter.
PATENTS ACT 1990
DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS
Re:Patent application 689484 by AIRSENSE TECHNOLOGY LIMITED, and opposition thereto, under Section 59, by VISION SYSTEMS LIMITED.

BACKGROUND

AirSense Technology Limited ("AirSense") filed patent application 689484 on 1 August 1994. The application claims priority from a GB application filed 30 July 1993. Patent application 689484 was advertised accepted on 2 April 1998.
Vision Systems Limited ("Vision Systems") filed a notice of opposition on 1 July 1998. A statement of grounds and particulars in support of the opposition followed on 1 October 1998. Vision Systems subsequently amended that statement several times primarily to bring the statement in line with the evidence filed.
On 4 August 1999 AirSense made a request to amend the application. An amended schedule of proposed amendments, dated 18 August 1999, proposed a substitution of all the claims with new claims 1-7. There was no opposition to the proposed amendments. Allowance of the request was advertised on 6 April 2000.
The documentary evidence in this opposition is voluminous. That evidence consists of evidence in support from Vision Systems, evidence in answer from AirSense, evidence in reply from Vision Systems, several stages of further evidence under Regulation 5.10(4) from both parties, and consequential evidence in response from both parties. Much of the further evidence and responding evidence related to the amended form of the application allowed in April 2000. The serving of all further evidence and evidence in response was allowed under Regulation 5.10(5) unopposed.
On 10 February 2004 Vision Systems requested the Patent Office to issue summonses under Section 210 to three of AirSense's declarants to appear for cross-examination. The Patent Office considered Vision Systems' request and issued the summonses the next day. In response AirSense claimed a lawful excuse not to comply with the summonses.
With the agreement of the parties, hearings on AirSense's claim to lawful excuse were held on 17 and 20 February 2004. On 23 February the deputy commissioner hearing the matter issued his decision, [2004] APO 4. The deputy commissioner did not accept the reasons provided by AirSense constituted a lawful excuse for the witnesses not to appear. He noted though that the possibility could not be excluded that one witness from the UK, Mr David Christopher Mitchell, may have a genuine medical or psychological condition preventing him from travelling to Australia, and that this would constitute a lawful excuse if appropriate medical evidence was provided. The deputy commissioner further noted that if such medical evidence were obtained, Vision Systems would then need to decide whether it wished to cross-examine by video-conference.
AirSense subsequently provided a medical certificate. The parties reconvened on 9 March 2004 before the deputy commissioner to make submissions on whether the certificate adequately provided lawful excuse for Mr Mitchell's non-appearance in person. The deputy commissioner concluded there was lawful excuse for Mr Mitchell not to appear in person, [2004] APO 5. The parties then proceeded to make arrangements to have Mr Mitchell cross-examined by video link.
A hearing of the substantive opposition was held from 15 to 19 March 2004 in Melbourne. Mr Barry Hess of counsel, instructed by Ms Doreen Perrin, patent attorney of Lesicar Perrin, represented AirSense. Mr Anthony Burrows, UK chartered patent agent for AirSense, and Mr Peter Fox, one of the inventors, were also present in an advisory capacity. Dr John Emmerson of counsel, instructed by Mr Ian Pascarl and Mr Nik Ramchand, solicitors of Blake Dawson Waldron, represented Vision Systems.
TRANSCRIPT
The parties arranged a transcription service for the duration of the hearing. A hard copy of the transcript was made available shortly after each of the hearing sessions. This has been extremely helpful and I appreciate the parties' provision of this service.
THE SPECIFICATION
The specification states the invention relates to data processing apparatus and methods and to apparatus and methods for detecting the content of impurities in a gaseous medium. The invention has particular application for the detection of smoke from a fire. To prevent the internal parts of the detector from becoming contaminated, a filter is employed to remove larger particles than those anticipated with products of overheating materials. An acknowledged problem with prior smoke detectors is the tendency for filters themselves to become contaminated through use. This reduces the sensitivity of the detector over time. Frequent filter servicing is thereby required to maintain the performance of the detector.
The solution offered by the claimed invention is to provide a duct arrangement where a main duct functions as a sampling duct of a smoke detection system. There is a secondary duct receiving only a part of an air stream flowing through the main duct. A particles filter and detector are disposed in the secondary duct, the latter detecting the content of an impurity in the air flowing in the secondary duct. Much of the air flowing through the main sampling duct bypasses the filter and detector in the secondary duct thereby reducing the level of contamination of the filter and detector. This increases the service intervals for those components.
The specification ends with 7 claims. Claim 1 reads as follows.
1.A method of detecting content of an impurity in a stream of air flowing through main duct means in the form of sampling duct means of a smoke detection system, comprising causing only part of said stream to flow into secondary duct means, filtering said part of said stream through a particles filter disposed in said secondary duct means, and detecting, by detecting means downstream of said filter, the content of said impurity in the air in said secondary duct means.
Claim 3 is an apparatus claim corresponding with the above method claim.
STATEMENT OF GROUNDS AND PARTICULARS
The statement of grounds and particulars as amended asserts the following. The claimed invention is prior published or otherwise prior disclosed or prior used, or is otherwise not novel or lacks an inventive step. The claimed invention is not patentable because it is not a manner of manufacture. AirSense is not entitled to the grant of a patent for the present alleged invention. The claimed invention is a mere working direction.
Vision Systems provided numerous particulars to support each of the above grounds of opposition.
EVIDENCE
Vision Systems has served evidence from the following declarants:-
Martin Terence Cole                Peter Frederick Johnson  Keith Leslie
Kjell David Jawerth                 Michael John Scully  Frank Trubshaw
Raymond Michael Walsh         Michael William North             Harold James Piik-Wakeling
Ronald Knox  David Roy Packham  Russell John Cooper
George Barry Hubber              Zsuzsanna Csuthi  Ian Clarence Shepherd
Yonggang Zhu  Alasdair James Williamson                  Jonathan Paul Miles
AirSense has served evidence from the following declarants:-
Peter David Fox Alasdair James Williamson David William Barrett
Christopher Girling David Christopher Mitchell
Mr Williamson served evidence in answer for AirSense early in the opposition but subsequently gave further evidence for Vision Systems.
For Vision Systems, Mr Scully, Mr Trubshaw, Mr Walsh, Mr North, Mr Knox and Mr Cole gave significant evidence on entitlement and to some extent on the other grounds of opposition. Vision System’s remaining declarants gave evidence on the grounds of opposition other than entitlement.
For AirSense, Mr Fox, Mr Girling, and Mr Mitchell gave evidence on all the grounds of opposition. Mr Barrett and Mr Williamson predominantly gave evidence on the grounds other than entitlement.
The declarants summoned for cross-examination by Vision Systems were Mr Fox, Mr Barrett and Mr Mitchell. Mr Barrett and Mr Fox appeared in person in that order on 16 March. Mr Mitchell appeared via a video link the next day.
BACKGROUND TO THE DISPUTE
Much of the documentary evidence relates to activities taking place at IEI (UK) Ltd, predecessor subsidiary of Vision Systems, allegedly in the year before the priority date of the application. Vision Systems asserts its evidence shows that Mr Scully built a certain prototype smoke detection system at IEI's UK premises, and that this system was seen by employees and customers. Consequently the invention is not new. The prototype is known as the modified LOCATOR system. Mr Scully states the prototype was part of IEI (UK)'s attempt to secure a large contract in the UK for the supply and installation of smoke detection systems for a company called Glaxo. Vision Systems further asserts the present invention is based on Mr Scully's work at IEI (UK) and on Mr Fox's and Mr Girling's knowledge of Mr Scully's work, and on Mr Fox's and Mr Girling's own work whilst they were employed at IEI (UK). Consequently Vision Systems asserts that AirSense is not entitled to a patent for the invention.
CREDIBILITY OF WITNESSES
During cross-examination, Mr Barrett and Mr Mitchell both gave carefully considered answers. Where either of the witnesses did not know or could not recall an event, or could not understand a question, they said so. They were also neither evasive nor hostile. There were a few inconsistencies between the witnesses' oral evidence and their documentary evidence. For instance, in Mr Barrett's case, there was initially some discrepancy in Mr Barrett's statement, during cross-examination, of the group or division he worked for at IEI (Australia) compared with statements in his curriculum vitae. However this was resolved during re-examination of Mr Barrett where it was determined that Mr Barrett worked for two groups at different stages of his employment at IEI. It appears that, during cross-examination, Mr Barrett gave an incomplete answer either through wanting to be expedient or through misunderstanding the question. Overall Mr Barrett's and Mr Mitchell's oral evidence was consistent with their documentary evidence. I conclude that Mr Barrett and Mr Mitchell presented themselves as credible witnesses.
Mr Fox founded AirSense soon after leaving IEI (UK)'s employ. It is also notable that Mr Fox was the managing director at IEI (UK). Mr Fox underwent more rigorous cross-examination than Mr Barrett or Mr Mitchell on the knowledge and experience he took with him from IEI. Like Mr Barrett and Mr Mitchell, Mr Fox gave carefully considered answers. Again if he did not know or could not recall an event, or did not understand a question, Mr Fox said so. I similarly did not detect any evasiveness or hostility in Mr Fox's demeanour. Rather, Mr Fox appeared extremely nervous at first. I formed the impression he treated the hearing and the cross-examination process with a very high degree of respect and seriousness.
One inconsistency in Mr Fox's oral evidence appeared to be a statement that he was not working on the filter contamination problem at IEI. Subsequently Mr Fox openly acknowledged that he made use of his knowledge from IEI in his subsequent work on that problem at AirSense. From Mr Fox’s presentation at the hearing, I formed the view that this inconsistency could be put down to Mr Fox's misunderstanding of the original question rather than a deliberate misleading of the facts. Mr Fox’s open acknowledgement of his use of knowledge from IEI is also at odds with Vision Systems’ challenges of Mr Fox's credibility. I conclude that Mr Fox presented himself as a credible witness.
I conclude I have insufficient cause to doubt the veracity of the evidence of AirSense's witnesses.
ENTITLEMENT
The thrust of Vision Systems' opposition under this ground is that AirSense, through Mr Fox and Mr Girling, obtained the invention from IEI.
The Modified LOCATOR System at IEI (UK)
The original LOCATOR system is based on a hunting rotary valve product built by ICAM Limited, Mr Williamson’s company, and incorporated in a smoke detection apparatus at IEI (UK). Mr Cole tendered evidence, as exhibit MTC-19, of certified approval in October 1991 of the system.
I have concluded above that AirSense's witnesses are credible. Consequently Mr Fox's and Mr Mitchell's evidence that they never saw Mr Scully's prototype modified LOCATOR system at IEI (UK)'s premises while they were employed by IEI is plausible. Similarly I have no reason to doubt Mr Girling's statements on this point.
On the face of it Vision Systems' evidence of the existence of the modified LOCATOR system is also plausible. This would appear to suggest the modified LOCATOR system was installed at IEI (UK) after Mr Fox, Mr Mitchell and Mr Girling left IEI (UK). On the other hand several of Vision Systems' declarants state the modified LOCATOR system was installed and seen by them around April or May 1992. Two of these declarants, Mr Walsh and Mr North, are independent declarants from Wormald Brittania. The period April or May 1992 was prior to the departure between October 1992 and 1994 of all of Mr Fox, Mr Mitchell and Mr Girling from IEI (UK). Since Mr Fox was managing director at IEI, one would at least expect him to have been aware of the modified LOCATOR installation if it were there during his employment. At the hearing Mr Fox accepted this expectation. Mr Mitchell also stated in evidence that he would have been aware of the installation if it were there whilst he was employed at IEI (UK).
At the hearing there appeared to be some conjecture regarding Mr Girling’s departure from IEI (UK) to join AirSense. Mr Girling variously stated in his evidence that he left IEI (UK) in February 1993 or in the spring of 1993. AirSense consistently submitted that Mr Girling left IEI (UK) in February 1993. On the other hand Vision Systems equated the northern hemisphere spring as March to May 1993. Vision Systems stated this is very close to the claimed priority date of the present application for which Mr Girling was listed as a co-inventor and consequently Mr Girling must have taken significant current knowledge leading to the claimed invention with him from IEI (UK) to AirSense.
I think very little turns on this. Irrespective of whether Mr Girling’s departure was February, or March to May of 1993, the months are adjacent and all very close to the July 1993 priority date of the present application. I would expect Mr Girling’s knowledge from his work at IEI (UK) would have been similar on leaving that firm irrespective of whether that departure was in February 1993 or a few months later.
In any case, for the sake of completeness, I determine Mr Girling’s departure as follows. I understand there is some general acceptance in the UK that February is the end of winter and the start of spring. This would appear to suggest that Mr Girling’s evidence would not be incongruent. Furthermore there are at least two occasions in Mr Girling’s evidence where Mr Girling states he left IEI (UK) in February 1993. While Mr Girling may be criticised for being less precise in other parts of his evidence in referring to the spring of 1993 as the time of his departure, the fact that he states at least twice that he left IEI (UK) in February 1993 would appear to carry strong weight. I will accept February 1993 as the time that Mr Girling left IEI (UK). In any case, if the modified LOCATOR installation had been made, I expect Mr Girling too would have seen it.
Towards the end of the hearing I suggested that one could readily accept the relative ease of witnesses recalling whether they saw or did not see the modified LOCATOR system. However for those who saw the system, it would appear far more difficult to recall when it was that they saw it. I noted the passage of time between the first evidence being presented on this system and the alleged time of the installation. The first evidence on this subject is from Mr Scully and Mr Trubshaw, in the evidence in reply, and is dated December 1999, more than seven years after the alleged installation. At the hearing I put the possibility to the parties that the declarants' recollection of the timing of the installation may have faded after such a lengthy passage of time between installation and the serving of evidence on the subject. For instance, one declarant, Mr Williamson altered, in a subsequent declaration, the year of IEI (UK)’s bid for the Glaxo project from 1991 to 1992. One would also expect that around 1992 the timing of the installation would have been an insignificant issue of little value in remembering.
Dr Emmerson emphasised the counter argument of the consistency of several of Vision Systems' declarants stating the installation occurred in April, May or June 1992. Mr Trubshaw states that Mr Scully installed the test system for the Glaxo project around April 1992. Mr North and Mr Walsh, from Wormald, both comment on viewing the test installation at IEI(UK)'s premises around May 1992. This would appear to be strong evidence of the installation occurring at the time indicated. Mr Trubshaw and Mr Scully also both state that IEI (UK) first became aware during 1991 of Glaxo’s wishes for a comprehensive fire protection system at a site in the UK. The timing of a prototype around April, May or June 1992 thus appears to be plausible.
Counter to that is Mr Fox's 1992 diary tendered in evidence. The first indication in the diary of the existence of the Glaxo project is 13 July 1992 where Mr Fox indicates a meeting took place between Mr Walsh, Mr North and a Mr Steve Sage in respect to the Glaxo project. Mr Fox explains in his evidence that Mr Walsh is erroneously entered in the diary as Ray North. If this is the first knowledge of the Glaxo project then one would expect the development of prototypes by IEI (UK) staff to occur well after that date.
Dr Emmerson submitted the diary is inconclusive about first knowledge of the Glaxo project. All the diary indicates is that a meeting took place on that date with some key personnel. I accept Mr Fox's 1992 diary may be incomplete in respect to first contact with these and other personnel on the Glaxo project. Furthermore Mr Fox's diary for 1991 was not tendered in evidence. I conclude the 1992 diary is insufficient to establish that first knowledge at IEI (UK) of the Glaxo project was after the alleged April to June 1992 period of Mr Scully’s prototype.
Documentary Evidence of the Modified LOCATOR installation

Mr Scully’s documentary evidence of the modified LOCATOR installation at IEI (UK) consists of several exhibits. A design memo (exhibit MJS-3) written by Mr Scully describing the system application, a subsequently drawn sketch of the system (MJS-4), an even later and supposedly clearer diagram of the system (MJS-5), Mr Scully’s design memo with the sketches allegedly originally accompanying that memo (MJS-11), and a copy of a facsimile (MJS-12) by Mr Scully and addressed to IEI’s USA office.
Exhibit MJS-12 is a facsimile with a very rudimentary sketch of a prototype. The facsimile states a "mock-up" was done. One would need to presume the "mock-up" is in respect to the modified LOCATOR installation to draw the link between the facsimile and the installation. Mr Scully states in his corresponding declaration that is the case. AirSense did not seriously challenge the supposed link. I will take the link to be established.
The facsimile is dated 26 February 1993 and was sent by Mr Scully to IEI’s US office on 1 March 1993. ICAM’s Mr Williamson also gave evidence of receiving a copy of the facsimile. This is the only exhibit in Vision Systems' evidence with the entry of a firm date supposedly in respect to the modified LOCATOR installation.
In his declaration accompanying design memo MJS-3, Mr Scully stated he no longer had the sketches referred to in the memo. Exhibits MJS-4 and MJS-5 are subsequently made sketches representing to the best of Mr Scully’s recollection what was shown, particularly by sketch C referred to in design memo MJS-3. In his declaration accompanying MJS-11 and MJS-12, Mr Scully stated the solicitors for Vision Systems have provided him with a true and complete copy of his design memo and its accompanying sketches. Mr Williamson presented evidence of having received the same memo and sketches from Mr Scully in the first half of 1992.
Mr Scully states in his first declaration (1999) that the computer file of the memo MJS-3 was saved on 27 April 1992. There is no independent verification or evidence of the saving of the memo on that date. Mr Scully then states the memo was passed directly to Mr Trubshaw, IEI (UK)’s sales officer, on or immediately after that date. Mr Scully further states he understood that, in accordance with usual IEI (UK) company practice, the memo and sketches would also have been passed on to Mr Fox, to Wormald representatives and probably also to Glaxo representatives.
Much is made by Vision Systems of Mr Scully allegedly passing on to Mr Fox the design memos and sketches of the modified LOCATOR through Mr Trubshaw. It is noteworthy though that Mr Scully’s comments in his declaration are written in the passive in respect to the passing or distribution of this documentation to IEI (UK) personnel and others. He states the memo was passed, and the memo and sketches would have been passed to various personnel. Furthermore he makes assumptions, for example, that the material was probably passed to Glaxo representatives. Mr Scully’s declaration contains nothing categorically stating that he gave or showed any of this material to anybody.
Mr Trubshaw in his first declaration says Mr Scully showed the design memo and sketches to him and that Mr Trubshaw showed them to Wormald representatives. However Mr Trubshaw is notably silent on passing the material on to Mr Fox or to Mr Girling.
Mr Hess stated the passing of this material by Mr Scully or Mr Trubshaw on to Mr Fox and Mr Girling did not occur because the material post-dates the departures of Mr Fox and Mr Girling from IEI (UK). To support this statement Mr Hess suggested exhibit MJS-3 is couched in terms indicating the Glaxo project was well underway.
Mr Fox left IEI(UK) in October 1992. Mr Girling left in February 1993. I have also determined earlier that Mr Fox’s 1992 diary was inconclusive to establish the starting date of IEI’s involvement in the Glaxo project was as late as July 1992. Furthermore the description of the project being well underway is a relative term. Even if the starting date was as late as July 1992, one would expect the description, that the project was well underway by the time of Mr Fox’s departure, may be apt.
For exhibits MJS-4, 5 and 11, Mr Hess suggested these exhibits even post-date the priority date of the present application. I agree it appears inconclusive whether these sketches were made before the priority date of the application. I accept these exhibits carry little probative value. For the sake of completeness I will nonetheless consider their disclosure later.
In the absence of any of Vision Systems’ declarants conclusively stating they gave any of the material making up the Scully exhibits to Mr Fox, and in the light of Mr Fox’s statements, in his written evidence and at the hearing, that he had not seen it, I can only conclude the supposed passing of this material to Mr Fox did not occur.
Similarly Vision System’s declarants are silent on giving any of this material to Mr Girling. Mr Girling noted this point. I conclude the passing of this material to Mr Girling also did not occur.
Timing of Modified LOCATOR installation
The question remains as to when the installation was made. From the date of the copy of the facsimile MJS-12 by itself, one might infer the installation was sometime before 26 February 1993. Both Mr Fox and Mr Girling had left IEI by or in February 1993. Consequently I regard the facsimile as inconclusive in establishing that either person had seen the installation whilst employed at IEI.
It is also curious that there is no evidence of Mr Scully showing or discussing the modified LOCATOR installation directly with Mr Fox or Mr Girling, or at least drawing Mr Fox's or Mr Girling’s attention to the modified LOCATOR installation itself. I put this to the parties at the hearing. Dr Emmerson referred me back to the consistent evidence of Vision Systems' declarants that the installation was in May or June 1992 and that Mr Fox and Mr Girling must have seen it. Mr Fox further stated during cross-examination that if he had seen the installation he would have known what it was. Dr Emmerson appeared to rely on this statement to assert the installation did not need to be pointed out to Mr Fox. Nonetheless IEI (UK) regarded the Glaxo project as a significant project for IEI (UK). I would think a test prototype for that project would have been worth discussing or demonstrating with senior personnel at IEI (UK). Vision System’s evidence is significant in its complete silence of Mr Scully discussing the modified LOCATOR installation directly with Mr Fox or with Mr Girling.
That leaves a further scenario. That is, that the modified LOCATOR was installed in May or June 1992, as stated by Vision Systems' declarants, but at a time when Mr Fox, and Mr Mitchell and Mr Girling, were absent from IEI (UK)'s premises. From the evidence Mr Mitchell was often away on commissioning work. Mr Girling was the technical director and development engineer, and was at the premises most of the time, although occasionally absent. Mr Fox was often away on business.
It would appear to be quite a coincidence if the system was installed during the absence of all three declarants. If this is the case it is again curious that there is nothing before me indicating that Mr Scully made at least Mr Fox, as managing director, aware of the prototype itself upon Mr Fox's return.
On the other hand it seems plausible that Mr Scully may have installed the modified LOCATOR deliberately at a time to coincide with the absence of at least Mr Fox from the premises. The evidence from both parties indicates substantial acrimony between Mr Cole, then chief executive officer of IEI's parent company in Australia, and Mr Fox in respect to the smoke detection system to be offered for the Glaxo project. The evidence shows Mr Fox had gained acceptance from Wormald Brittania, preferred installers for Glaxo, for use of IEI's E7 Az-Pyr system. Mr Cole vetoed the supply of that system for the Glaxo project in favour of a LOCATOR System. Mr Fox also stated in evidence that if he had seen the modified LOCATOR prototype installed and linked to the premises' fire alarm system he would have ordered the prototype to be removed. I have also noted examples earlier of Mr Scully’s passiveness and indirectness in his working relationship with Mr Fox at IEI (UK). In the light of the above, I would regard it as unsurprising if Mr Scully worked on and installed a modified LOCATOR system deliberately at a time when Mr Fox was absent.
I conclude the latter to be the most plausible scenario. That is, the modified LOCATOR system was installed at IEI (UK)'s premises around May or June 1992 but at a time when Mr Fox and Mr Girling and Mr Mitchell were absent from the premises.
Whether the Modified LOCATOR Leads to the Claimed Invention
Even if Mr Fox and Mr Girling had seen the modified LOCATOR at the alleged time of installation, it would still need to be established that the invention, as claimed in the present application, derived from that installation.
There appear to be several differences in Mr Scully’s exhibits on the modified LOCATOR. Mr Hess noted and referred to Mr Fox’s discussion of these differences during re-examination. Exhibits MJS-4 and MJS-5 show the entire sampled air passing through a filter whereas MJS-11’s sketch C and MJS-12 show no filter at all. MJS-5 shows specifically an exhaust pipe or outlet from the refined E70D cabinet whereas MJS-4 exhausts the cabinet from the aspirator. The exhaust of MJS-5 is also different from that of sketch C. In the latter there is a pipe with a flow sensor from a pump to the exhaust outlet whereas in MJS-5 there is no connecting pipe between the aspirator and the exhaust. In sketch C there is also a LOCATOR sampling point upstream and separate of the exhaust, and not at the outlet point at the wall of the cabinet as in MJS-4 for example.
The above exhibits from Mr Scully contain notable discrepancies between them in respect to the modified LOCATOR. This leaves serious doubts as to what the prototype built at IEI (UK)’s premises actually consisted of. I can at best conclude from some commonality of features identified in the various Scully exhibits that the modified LOCATOR installation consisted of a LOCATOR sampling point to monitor the outlet of an aspirating fan. The sampling pipe was output to the LOCATOR unit. One would need to presume the LOCATOR unit is the same or similar unit as that exhibited by Mr Cole as exhibits MTC-18 and MTC-19. Prima facie that appears to be the case. Both Mr Cole’s and Mr Scully’s exhibits illustrate that unit as a multi-tube detector that samples the tubes individually.
This arrangement is a long way short of clearly disclosing a main duct means in the form of sampling duct means, and a secondary duct means having filter and detector unit receiving a portion of the air flowing through the main duct means as claimed in the present application.
I conclude the evidence is insufficient to show that, through the modified LOCATOR installation, AirSense obtained the claimed invention from IEI.
Alleged Obtaining of Invention from E7 Az-Pyr development
Mr Knox provided evidence (RK 19 to 21) of the E7 Az-Pyr development by Mr Fox at IEI(UK). He exhibited copies of correspondence between Mr Cole and Mr Fox regarding that detector unit. The correspondence took place in October 1992. The thrust of the correspondence is that Mr Cole requested Mr Fox to withdraw this detector system as a formal offer for the Glaxo project because it was an unproven product.
Mr Fox commented in his evidence that it may well be that Mr Cole regarded the pre-production model of the E7 Az-Pyr as unproven. Mr Fox however noted that it was the chosen product by the contractors, Wormald and Ove Arup, for the Glaxo project.
The above suggests a strong association of Mr Fox with the E7 Az-Pyr unit. At the hearing Mr Fox accepted this. He stated he recalled very well the acceptance of the E7 Az-Pyr unit by Glaxo’s contractors for the Glaxo project.
Mr Cole presented a physical exhibit of the E7 Az-Pyr unit in evidence. Vision Systems further presented a drawing of the unit. The drawing has little probative value as it was made after the priority date of the application. Consequently I am obliged to give weight to the physical exhibit. In any case I will briefly compare the physical exhibit and the drawing.
The drawing is supposedly an enhanced and clearer view of the E7 Az-Pyr unit, especially the interior of the unit. The interior of the physical exhibit cannot be discerned as readily as illustrated in the drawing. Nonetheless a comparison of the two items yields some differences. Firstly the drawing shows the unit as a longer and flatter structure than the physical exhibit. Secondly the drawing appears to indicate the interior as a flow-through duct means surrounding a housing containing the filter and detecting means. The filter and detecting means cannot be viewed in the physical exhibit. In any case, the interior area supposedly of the main duct means does not appear to be as constricted in dimension to form a duct means as indicated in the drawing. The interior as per the physical exhibit is more in the nature of a chamber than a duct means. Furthermore it is not determinative that this duct means is in the form of sampling duct means. Given these differences, and the lack of probative value of the drawing, I disregard the drawing and consider only the physical exhibit.
I cannot tell from this exhibit whether a filter is present. Mr Cole does not allude to the presence or absence of a filter in his evidence either. I must conclude there is no clear disclosure of a filter in the detector module. Further I find it cannot be fairly said there is a main duct means in the form of sampling duct means, and a secondary duct means with filter and detecting means.
I conclude the evidence is insufficient to show AirSense, through the E7 Az-Pyr development, obtained the claimed invention from IEI.
Employment relationships
Even if the alleged invention could be said to derive from Mr Fox’s or Mr Girling’s activities and knowledge at IEI (UK), it then needs to be established that Mr Fox or Mr Girling were obligated by contract or employment to IEI (UK) such that AirSense’s application for the alleged invention rightfully belonged to IEI (UK), now Vision Systems.
The law is replete with cases on entitlement issues in respect to employer and employee relationships. The Aneeta Window Systems (VIC) Pty Ltd v K Shrugg Industries Pty Ltd decision, (1996) AIPC 91-249, cites several British decisions to state an established principle of law. The principle is that where an employee in the course of their employment makes an invention which was part of their duty to make, the law imports into the contract of employment a term that the invention is the property of the employer.
It is noteworthy that neither Mr Fox nor Mr Girling was working for IEI (UK) at the priority date of the present application. On the face of it their terms of employment had concluded and they were no longer obligated to IEI (UK).
Much was made by Vision Systems in evidence and at the hearing that Mr Fox and Mr Girling took what they knew from IEI (UK), founded AirSense, and marketed and sold the present invention under the AirSense name. Even if this were true, there is nothing in Vision System’s evidence to show IEI (UK) had restrained Mr Fox or Mr Girling from doing that. Vision Systems has presented no evidence that Mr Fox or Mr Girling were under any restriction under their employment termination conditions, as far as the use of their knowledge from IEI (UK) was concerned.
Dr Emmerson questioned Mr Fox somewhat at the hearing on Mr Fox regarding himself a free agent after leaving IEI (UK). In answer to one such question Mr Fox categorically stated he was a free agent. Mr Fox said IEI (UK) attempted to restrict his activities and employment prospects in the industry after the termination of his employment at IEI (UK). However under the terms of Mr Fox’s unfair dismissal case against IEI (UK), such attempts by IEI (UK) were unsuccessful.
I conclude Mr Fox, and Mr Girling, had no obligations to IEI (UK) after leaving that company.
I conclude the evidence is insufficient to disqualify AirSense from entitlement to the claimed invention.
PRIORITY DATE OF THE CLAIMS
Vision Systems asserted the claims of the application are not entitled to the claimed priority date of 30 July 1993. If this is correct then one of AirSense’s technical manuals, dated April 1994, may be relevant prior art.
Vision Systems stated the GB priority document of 30 July 1993 did not disclose the alleged invention as claimed. Vision Systems relied on the CCOM Pty Ltd v Jiejing Pty Ltd decision, (1994) 28 IPR 481, amongst others, in support, quoting from CCOM (supra) at page 504:
“Certainly, the Australian case law includes examples where there has been a lack of fair basing because of the total silence of the basic application as to a feature of the invention as claimed. That is but another way of saying that there cannot be a real and reasonably clear disclosure if there is no disclosure.”
Vision Systems submitted that both the GB priority application and the present application as filed are directed to several different methods and apparatus. These include data processing, signal analysis, radiation sensing aspects of the detecting means, and statistical analysis related to detected impurities in a gaseous medium. Vision Systems argued that aspects such as the secondary duct means, and the filtering of part of the stream through a particles filter, were either not disclosed in either of the above applications or were not relevant to the thrust of the inventions described in those applications. Consequently Vision Systems asserted the claimed invention is not fairly based on the disclosures in those applications and cannot claim priority from those applications.
It may be that the GB priority document and the present application as filed have a different emphasis. On the other hand the test is not whether the earlier documents emphasise different aspects from what is now claimed in the present application. According to CCOM (supra) the need is that there should be a real and reasonably clear disclosure of the claimed invention. In the present case the fluid flow aspects of the invention seem to occur no earlier than the sixth or seventh aspects in the GB document or the application as filed. So long as adequate disclosure as per the CCOM test is in the earlier documents irrespective of how far into the documents that disclosure occurs, it seems that, according to the CCOM test, the presently claimed invention would be fairly based on the earlier documents.
Vision Systems has taken particular objection to three features of the invention as now claimed. The first is the claiming of the secondary duct means in various guises in the claims. The GB priority document describes branch duct means rather than secondary duct means. Vision Systems relied on Webster’s Revised Unabridged Dictionary to state the phrase ‘to branch out’ meant ‘to form a branch or a separate part; to diverge’.
On the other hand there is ample support requiring a specification to be read as a whole and be given a purposive construction. See for example Rosedale Associated Manufacturers Ltd v Carlton Tyre Saving Co Ltd, (1960) 77 RPC 59, Welch Perrin and Co Pty Ltd v Worrel, (1961) 106 CLR 588, Catnic Components Ltd v Hill & Smith Ltd, [1982] RPC 183, and Décor Corporation Pty Ltd v Dart Industries Inc, 13 IPR 385.
In the present case the GB priority document, at page 8 line 13 onwards, describes a “bypass arrangement”. That is, a large proportion of the air, via the main duct means, bypasses the filter and thus the detector downstream of the filter in the branch duct means. In this context it is clear that the branch duct means should not be interpreted, as narrowly as Vision Systems submits, to a means that only diverges. I consider this interpretation is taking the GB document out of context, and is engaging in the sort of meticulous verbal analysis that the Catnic Components (supra) decision warns against. Instead the GB document clearly discloses that the branch duct means branches from the main duct means and may then come together again downstream with the main duct. I conclude there is adequate support for the secondary duct means in all its forms in the claims of the claimed invention.

The second feature that Vision Systems objected to is the claiming of part of the stream being filtered through a particles filter. Vision Systems asserted that the invention in both, the GB document and in the present application as filed, is directed to improving the response time of the detecting means and prolonging the service life of the detector. The filter, according to Vision Systems, is irrelevant.
On the other hand the previously mentioned passage of the GB document, beginning at page 8 line 13, mentions a smaller, representative sample of the air passing through a filter. Again I find adequate support for this aspect of the claimed invention.
The third feature that Vision Systems objected to is the claiming of a detection module in claims 2 and 4 of the present application. Vision Systems asserted there is no disclosure or suggestion in the GB document that any of the components of the system can be enclosed in a module. Vision System further argues that as the GB document states that air is drawn into an enclosure for the smoke detector with a large proportion of air not entering the filter, then the enclosure must be the main duct means. If the enclosure were the module then there would be no disclosure of a main duct means.
It seems to be correct that the word “module” does not appear in the GB document. Again though I think Vision Systems is engaging in the meticulous verbal analysis that the Catnic Components (supra) decision warns against. Vision Systems has taken one passage from the GB document to suggest the enclosure equates with the main duct means. This is a tenuous equating of features. The GB passage states (again on page 8) that “as the air stream is drawn into an enclosure for the smoke detector, a large proportion of the air is vented…. without entering the filter”. Rather than stating that all the air is vented, this statement seems to clearly imply something else happens with the remaining portion of air within the enclosure. The next sentence in the GB document explains that portion of air passes through the filter. I think it is clear that the enclosure of the GB document encloses both the main duct means and the branch duct means there within. This appears to be consistent with the claimed detection module of the present application. I conclude there is adequate support for this aspect of the claimed invention.
FAIR BASIS OF CLAIM 5
The fair basis of claim 5 of the application, and claim 5’s entitlement to the earliest priority date, were challenged for the following reasons.
Vision Systems submitted the powered means of claim 5 had no basis from the descriptions of any of the GB document, the present application as filed or the present application as it presently stands. Furthermore Vision Systems stated the term had no inherent meaning, or any antecedent in any preceding claim.
AirSense submitted the basis for the term is the fan on page 10 of the present specification at line 6. The fan is described as drawing air from a room and forcing it through the ducting.
At present the powered means is defined in isolation from any of the other components of the apparatus apart from being located upstream of the secondary duct means. There is no clear juxtaposition of the powered means with other components. There is also no definition of the nature of the powered means, the nature of the power it produces, nor of what is being powered. Whilst a fan may fall within the bounds of powered means, the latter term may encompass significantly more, for instance any mechanical power, or electrical power generation. In this field it may include electric or battery-powered signal generating means, detecting means or alarm generators. If the intention is that the powered means defines a fan as one embodiment then the term “powered means” is clearly broader than this. From reading the specifications as a whole, that term is well beyond anything described in any of the specifications. I think an amendment to bring the description in line with the claim would not remedy the situation. As a minimum I would expect the claim to at least define a mechanical powered means located in the main duct means and upstream of the secondary duct means, and that forces air through the ducting, the filter and detector unit to enable rapid detection of smoke. Claim 5 is clearly flawed as it presently stands.
If the term “powered means” were interpreted narrowly to a mechanical means of forcing air through a ducting then there may be a basis for assigning the claimed priority date of 30 July 1993 to claim 5. On the other hand, the interpretation of that term as any type of mechanical powered means or as any electrical powered means, such as a battery, means the earliest possible priority date of claim 5 is 1 August 1994, the date of filing of the application.
I conclude that claim 5 is not fairly based on any of the above-mentioned documents. Furthermore the term “powered means” can take several divergent meanings and consequently is not clear. The term also has no antecedent in any preceding claim.
I conclude that all claims, apart from claim 5, are entitled to priority from the GB priority document.
NOVELTY
The Meyers Taylor Pty Ltd v Vicarr Industries Ltd decision, (1977) 137 CLR 228, provides an appropriate test for novelty. The test is also known as the "reverse infringement test". Aickin J., at page 235, states:
"The basic test for anticipation or want of novelty is the same as that for infringement and generally one can properly ask oneself whether the alleged anticipation would, if the patent were valid, constitute an infringement."
The Rodi and Wienenberger AG v Henry Showell Ltd decision, (1969) RPC 367, states that infringement occurs where each and every one of the essential features of a claim is taken.
A practical application of the above decisions suggests a claim lacks novelty if a prior citation discloses all of the essential features of a claim.
Vision Systems cited, amongst others, the Bristol-Myers Squibb Company v FH Faulding & Co Ltd decision, (2000) 46 IPR 553 at 576, to assert that what the authorities contemplate is that a prior publication, if it is to destroy novelty, must give a direction or make a recommendation or suggestion which will result, if the skilled reader follows it, in the claimed invention.
I will apply these tests to the present case.
At the hearing Vision Systems principally relied on seven examples of prior art. Some of these relate to prior use as evidenced by physical exhibits and photographs of articles in use in the UK before the priority date of the application. Since the Patents Act 1990, as enacted at the priority date of the application, limited relevant prior use to use in Australia, then use in the UK is relevant only insofar as the existence of documented evidence before the priority date disclosing items or systems equivalent to that allegedly used in the UK. Vision Systems nonetheless also asserted prior use or publication in Australia of the above seven examples. In any case Vision Systems also supplied documentary evidence for these examples. This evidence was all declared by Vision Systems’ relevant declarants to pre-date the priority date of the application. AirSense did not seriously challenge the availability of these examples as prior art. I will take them to be prior art.
E700 Smoke Detection System
The E700 Very Early Smoke Detection Apparatus (VESDA) series was a series of detector systems manufactured by IEI. Mr Cole exhibited in evidence the brochures and the operating manuals for various versions of the E700 series. Numerous installations of the Mk II version in Australia and several other countries in the 1980s are documented in Mr Cole’s evidence.
Referring to the operating manual in Mr Cole's evidence for the Mk II version, the E700 comprises a detector unit with a dust filter upstream from there. A perforated sampling pipe in an air-conditioning duct for a room passes a sample of air through the filter to the sampling chamber of the detector unit.

100. Dr Emmerson stated the E700 system took part of the air in a room through the air-conditioning duct with a part of the air in that duct then being extracted and analysed. Dr Emmerson submitted there was consequently a main duct, in the form of a sampling duct, and a secondary duct that has itself a detector system in it as claimed in the claims of the application.
101. In support Vision System's declarants, principally Mr Cole and Mr Johnson, make the analogy that an air-conditioning duct is a main duct in the form of a sampling duct as claimed since it passes only a subset of the total air in a room.
102. Mr Hess asserted the claimed invention is distinguished from the E700. He noted AirSense's declarants stated an air-conditioning duct was not regarded in the industry as a main sampling duct of a smoke detection system. In support Mr Hess referred principally to Mr Fox's and Mr Barrett’s evidence in answer. They note the main duct means and secondary duct means both form part of the smoke detection system. Consequently it is inaccurate to suggest an air-conditioning duct is analogous to the main duct means of the claimed invention. In further evidence Mr Fox noted the amendments made to the specification after acceptance of the application were directed at avoiding the main duct means being interpreted as an air-conditioning duct. Mr Hess also noted the thrust of the claimed invention was that only a small proportion of the sampled volume from the main duct means passes through the filter and detection chamber.
103. Claim 1 of the application defines the main duct means of a smoke detection system. Dr Emmerson made numerous statements that the terms in the specification were not special terms of the art. That is, such terms should take their plain meaning. An air-conditioning duct's function is to convey humidified or de-humidified or temperature-controlled air (Webster’s Third New International Dictionary). The main duct means in the form of a sampling duct as claimed in the present specification is clearly defined as being of a smoke detection system. In this context, it is difficult to regard the air-conditioning duct as a main sampling duct of a smoke detection system.
104. I conclude the claimed invention is novel over the E700.
Olsen D51B Duct Sampling Unit
105. The Olsen unit samples air from an air-conditioning duct or similar into a chamber. A detector unit is positioned in this chamber and has a number of vents through which air can pass from the chamber through a filter into the detector unit. A baffle may be placed in the chamber diametrically over the detector unit.
106. As with the E700 it is difficult to regard the air-conditioning duct, from which the Olsen unit takes an air sample, as a main sampling duct of a smoke detection system as claimed in the application. This is a strained construction of the main duct means in the form of sampling duct means.
107. In the alternative Dr Emmerson offered several other interpretations suggesting the clear housing or chamber of the unit may be either the main duct means or secondary duct means as defined in the application. Webster’s Third New International Dictionary defines a duct as a passage, or a pipe, tube or channel by which a substance is conveyed. I think it would also be a strained interpretation to regard the housing of the Olsen unit as a pipe, tube or channel. On the other hand a passage may appear to take a more varied form than a pipe, tube or channel. Again with reference to the above dictionary, a passage is “a means of passing; a road, path, channel, or course through or by which something passes”. The housing though does not necessarily constitute a means of passing. Air may equally simply circulate within the housing. I think it is incorrect to regard the housing of the Olsen unit as a duct.
108. As a further alternative Dr Emmerson particularly referred to the physical exhibit of the Olsen unit and noted the baffle in the housing is not a tight fit over the detector unit. The baffle appears to be a piece of foam diametrically over the detector unit. It was suggested that the lack of a tight fit over the detector unit creates a passage in the form of a main duct between the baffle and the detector unit. The suggestion being that a majority of air flowing in the gap between the baffle and detector unit and a smaller proportion flowing through the vents in the detector unit to the detector itself is analogous to the operation of the main and secondary duct means, respectively, as claimed in the present application.
109. I accept there is no tight fit of the baffle over the detector unit. There is a gap over the detector unit for air to flow between the baffle and the detector unit. The issue then is whether this gap can be taken to be a duct. The baffle diametrically and perpendicularly lays over the detector unit. Again with reference to the above dictionary I consequently think it is incorrect on a plain reading of the terms to regard the gap as a pipe, tube or channel. A passage though is defined more broadly as a means of passing. Consequently I think the gap in the Olsen unit may be said to be a passage. This suggests the gap between the baffle and the detector unit could be regarded as a duct. Similarly the vents accepting a portion of the air into the detector unit could be regarded as ducts.
110. AirSense suggested there is no secondary duct means in the Olsen unit and this is not altered by identifying an inadvertent gap between the baffle and the detector unit for air to flow and calling that a main duct means. On the other hand Vision Systems argued the baffle and the gap created by the baffle was not inadvertent. Vision Systems noted that many Olsen units had been sold with and without the baffle, so the placing of the baffle and creation of the gap was deliberate. The Olsen literature stated the prevention of air from bypassing the detector was the reason for including the baffle.
111. It seems to be largely irrelevant as to whether the gap is intentional or not. If the gap enables air to flow between the baffle and the detector unit then the gap seems to fall within the meaning of being an air passage. However the statement that the reason for the baffle was to prevent air from bypassing the detector suggests that the vents in the detector unit are the primary duct means, not the secondary duct means. This view also appears to have support from the overall construction of the Olsen unit. The vents in the detector unit dominate over the size of the gap between the baffle and the detector unit. As the secondary duct means are claimed to contain the filter and detector, then the Olsen unit does not read onto the claimed invention in this respect.
112. The claimed invention further requires a main duct means, in the form of sampling duct means, that takes the flow of an air stream, and secondary duct means, with a filter and detector, that takes part of that stream. I think the Olsen unit cannot be said to disclose a sampling duct taking a stream of air with part of that stream then flowing into the detector unit. Rather there are two separate streams of air, directed either through the gap between the baffle and the detector unit, or directed through the vents in the detector unit.
113. I conclude the claimed invention is novel over the Olsen unit.
Autronica Autrosense BW-50
114. This device has some similarities with the Olsen unit. There is a chamber receiving air through an inlet. Ribs on two detector types within the chamber receive a portion of the air flowing in the chamber. Annular filters within the detectors filter air entering the ribs. Filtration occurs upstream of the detector sensors.
115. AirSense stated the Autronica filter is a coarse weave suitable only for filtering insects or very large particles. Mr Barrett, for example, noted that this filter would not keep out dust, an essential requirement of a filter if the smoke detector were to function properly.
116. It may be that the particles filter envisaged by AirSense in the claimed invention is a very fine filter that filters dust but allows smoke particles through to the detector. On the other hand, the expression “particles filter”, in the claims of the application, has no inherent restriction regarding fineness of the filter. I conclude the coarse filter of the Autronica device falls within the scope of the term, “particles filter”.
117. Vision Systems asserted the chamber of the Autronica device defined a main duct means in the form of sampling duct means, and the ribs defined secondary duct means.
118. As with the Olsen unit though I think it is incorrect to regard the chamber of the Autronica unit as a duct. Consequently the Autronica unit cannot be said to have both a main duct means in the form of sampling duct means, and a secondary duct means with filter and detector therein. Rather the latter is the primary duct means in the Autronica unit.
119. I conclude the claimed invention is novel over the Autronica device.
US Patent 4073619
120. The specification for this patent describes a waste gas analyser for steel making operations. Referring to the only figure in the specification, a main sampling duct is disclosed that takes a sample of gas from a waste gas duct. Most of the sampled gas is exhausted to atmosphere at an exhaust point. A second sampling duct branches from the main duct before the exhaust point. Along the second sampling duct is a filter. Downstream from there are three gas analysers. The analysers are a paramagnetic oxygen analyser, and two infrared analysers, for carbon monoxide and carbon dioxide respectively. It may be argued, as AirSense has done, that gas detectors and gas analysers are completely different from smoke detectors in terms of having different specialisations. However the claimed invention broadly defines the detection of the content of impurities in air. Since the US Patent describes the analysis of waste gases it seems appropriate to regard any of the three analysers as components for detecting the content of impurities in an air stream as claimed in the present application. The distinguishing of detector unit types by itself does not save the claimed invention. What appears to save the claimed invention is the broad subject of the claims.
121. The structure disclosed in the US Patent is substantially identical to that claimed in at least independent claims 1 and 3 of the present application. On the other hand the structure in the US Patent is a waste gas analyser. There is no disclosure of the detection of an impurity in an air stream flowing through main duct means in the form of sampling duct means of a smoke detection system as claimed in the present application.
122. I conclude the claimed invention is novel over US Patent 4073619.
JP Patent Publication 2-173896
123. Exhibit DRP-15 to Mr Packham’s declaration of February 2001 is purportedly a copy of a full translation, made by a firm called Patro Information K.K., of Japanese patent publication number 2-173896. This translation discloses air being guided along a suction pipe to an aquatic filtering unit that removes environmental noise factors like vapour, oil mist and dust. The air then enters a smoke sensor. Specifically the smoke sensor is in the form of a sampling chamber.
124. Vision System’s declarants, Mr Packham, Mr Jaewerth and Mr Cole, surmise that the sampling chamber is a main duct means in the form of sampling duct means, and that the secondary duct means sits within and communicates with the main duct means. The declarants further surmise that only some of the air flowing through the main duct would enter the secondary duct, pass through a particles filter and reach the detector. At the hearing Vision Systems also provided enhanced and enlarged drawings, supposedly of the drawings of the JP patent publication to support these statements.

125. It is difficult to see the JP patent publication itself supporting these statements. The illustrated sampling chamber does not resolve the interior of the chamber clearly, much less to the level of detail surmised by Vision Systems. In the JP document it appears there may be channels surrounding a unit within the chamber. However there is no clear illustration of the air flow arrangements within the chamber or of the communication between the channels and the unit. The description of the sampling chamber in the body of the patent publication merely relates that either a light-scattering type or ionization-type smoke sensor is installed within the sampling chamber. There is insufficient disclosure in the JP document to anticipate the claimed invention.
126. I conclude the claimed invention is novel over JP 2-173896.
US Patent 3154733
127. Figure 3 of this document illustrates a fire alarm system. The system has a main duct with a secondary duct within the main duct. At the entrance of the secondary duct is a filter. Within the secondary duct are two electrodes. One of the electrodes is provided with radioactive material for partly ionizing the space between the two electrodes. These elements together may be said to form the ionization detector unit for combustion particles to be detected.
128. Vision System’s Mr Jawerth surmises the main duct is probably part of a sampling system. On the other hand there is no apparent description of the main duct in the body of the specification at all, let alone that it is a sampling duct or part of a sampling system. From the drawing and the description of the fire alarm system generally, the main duct appears to be a duct carrying a direct flow of air. I think there is insufficient disclosure of a main duct means in the form of sampling duct means of a smoke detection system as claimed in the present application.
129. I conclude the claimed invention is novel over US Patent 3154773.
Brown, Moores and Birkby paper.
130. This paper is titled “The early detection of fires in coal pulverising mills by measurement of carbon monoxide”, by J. Brown, N. Moores and C. Birkby. The paper (hereafter referred to as the Brown document) is exhibit KDJ-13 to Mr Jawerth’s declaration of July 2002. According to that evidence the paper was presented at a symposium in London in July 1972.
131. Vision Systems cited Figure 20.2 of the paper as the pertinent disclosure. This figure illustrates a probe drawing a sample from an air duct. A sampling line, labelled “Nylon sample line”, directs the sample towards a filter. A separate line upstream of the filter draws excess sample to waste. Downstream of the filter is a gas analyser.
132. Vision Systems submitted the initial “Nylon sample line” from the probe, and the excess sample to waste line form a main duct means in the form of sampling duct means. The filter and gas analyser line forms the secondary duct means in communication with the main duct means. Only part of the air flowing through the main duct is caused to flow through the secondary duct means.
133. There was some conjecture at the hearing and in the evidence in respect to the excess sample to waste line. Air Sense’s declarants, Mr Fox and Mr Girling, indicated that Figure 20.2 showed a valve in that line. They suggested this meant the flow through that line may be restricted or shut off. Consequently Mr Fox and Mr Girling regarded that line as a secondary duct, rather than a main duct, for instance to allow adjustment for pressure or flow rate. This interpretation would make the filter and gas detector line the main duct contrary to the claimed invention.
134. Vision System’s declarants, for instance Mr Jawerth, noted that, irrespective of whether the valve sets precise pressure or flow rates on the filter, there is nothing to suggest it only passes a small proportion of air or is closed during operation. Mr Jawerth states the essence is these systems generally are designed to pass as little air and contamination as possible to the filter.
135. There is a flow meter illustrated between the filter and the gas analyser. However there is no discussion in the text of the Brown document about the valve or other details of the excess sample to waste line, or of any regulatory activity in the flow in the two lines. Consequently I will take the function of the excess sample to waste line from a plain reading of what is disclosed by the drawing. It is described as an excess sample to waste line. This would seem to indicate that what is not needed for gas analysis is passed as excess through that line.
136. It was well understood in the art before the priority date, from AirSense’s admitted prior art in its specification and from the evidence generally, that detector life would be prolonged if only the necessary amounts of air to ensure detection of fires or smoke passed through the detector. I am prepared to accept the excess sample to waste line is analogous to the main duct means of the claimed invention.
137. The arrangement described by Figure 20.2 of the Brown document is similar to that for US Patent 4073619. The structure disclosed in the Brown document is substantially identical to that claimed in at least independent claims 1 and 3 of the present application. On the other hand the structure in the Brown paper is a fire detection apparatus specifically detecting fires by the presence of carbon monoxide. There is no disclosure of the detection of an impurity in an air stream flowing through main duct means in the form of sampling duct means of a smoke detection system as claimed in the present application.
138. I conclude the claimed invention is novel over the Brown document.
Stratos High Sensitivity Smoke Detector Technical Manual
139. This manual was presented in evidence by Mr Knox as exhibit RK-8. The manual was written by Mr Girling in his capacity as technical director for AirSense and is dated April 1994. Mr Fox also briefly discussed the manual in his evidence.
140. The manual is raised here only in respect to claim 5. I have earlier found that a broad interpretation of the term “powered means” in claim 5 renders that claim unable to take the earliest priority date of 30 July 1993 as that claim’s priority date. Claim 5’s earliest possible priority date is 1 August 1994, the date of filing of the present application.
141. The manual focuses on various detector types, air sampling or aspirating systems, and air impellor devices such as fans for drawing air along the ducting and through detector units. If the powered means of claim 5 were interpreted as an air impellor or similar mechanical powered means then, as noted earlier, claim 5 may be entitled to the July 1993 priority date. In such circumstances this disclosure in the Stratos manual is of no consequence against the invention as claimed in claim 5.
142. On the other hand the powered means can also be interpreted as an electrical powered means or any other type of mechanical powered means. With this interpretation I have found earlier that claim 5 can take no earlier priority date than 1 August 1994. Consequently the disclosure of the power supply arrangements near the end of the Stratos manual may be relevant.
143. There are various power supply options disclosed in the Stratos manual such as mains transformer and/or battery supply. On the other hand there is no clear disclosure in the manual of the juxtaposition of the power supplies with the ducting arrangements of the apparatus although one might surmise they are upstream of the secondary ducting as is suggested in claim 5. In any case the ducting arrangements generally are not clearly described. Mr Knox suggested in his evidence that page 13 of the manual discloses main and secondary duct samplers and that only a small part of the sample passed through the filter and detector. It also seemed to be acknowledged by AirSense that the Stratos detector and manual were reflective of the invention the subject of the application. On the other hand, all that is said at the cited passage is that only a small part of the total air sample need pass through the detector head. The detector will function equally well for a small sample as a big sample. Consequently only the small sample requires filtering and passing through the detector. The arrangements by which this is achieved are not clearly disclosed anywhere in the manual. Certainly there is no clear disclosure of the main and secondary ducting arrangements, and of filter and detector placement with the ducting arrangements, as claimed in independent claims 1 and 3 of the application.
144. I conclude the Stratos manual does not challenge the novelty of claim 5 even with the later priority date assigned to claim 5.
INVENTIVE STEP
145. Under section 7(2) of the Patents Act, an invention is taken to have an inventive step unless it would have been obvious to a person skilled in the art in light of the common general knowledge in the patent area before the priority date of the claims. Under section 7(3) the common general knowledge may be considered either on its own, or together with (relevantly) a single piece of prior art information which the skilled person could, before the priority date of the claim, be reasonably expected to have ascertained, understood and regarded as relevant.
146. Vision Systems cited the Wellcome Foundation Ltd v VR Laboratories (Aust.) Pty Ltd decision, (1981) 148 CLR 262 at 280, to state the question is whether the invention would have been obvious to a hypothetical skilled addressee armed with the common general knowledge at the priority date. Also from that decision at page 286, an appropriate test is whether a person skilled in the relevant field, and faced with the same problem, would have taken as matter of routine whatever steps might have led from the prior art to the invention.
147. Vision Systems further cited the Aktiebolaget Hassle v Alphapharm Pty Limited decision, [2002] HCA 59, applying Olin Mathieson Chemical Corporation v Biorex Laboratories Ltd, [1970] RPC 157, to state the question is:-
“[W]ould the notional research group … directly be led as a matter of course to try [the alleged invention] in the expectation that it might well produce a useful alternative”.
148. I will apply these tests to the present case.
The person skilled in the art
149. Vision Systems described the person skilled in this art as one skilled in the design and installation of fire detection apparatus. Vision Systems further asserted the gas detection, gas analysis and smoke detection industries are all closely allied. Whilst there may be diverse applications for gas detection and analysis systems, many uses come under the umbrella of fire detection as do smoke detection systems. Mr Knox, Mr Cooper, Mr Piik-Wakeling and Mr Hubber all mentioned examples of the alliance of the industries before the priority date of the present application. The examples included the commonality of parts used, the use of carbon monoxide detection for smoke detection, and the close relationship of the industries evidenced in industry training courses and fire protection handbooks.
150. AirSense described the relevant person more narrowly. That is, one skilled in a particular area of fire detection, namely skilled in smoke detection system design and installation. AirSense asserted it was incorrect to draw on skills or knowledge in the gas detection or gas analysis industries for smoke detection purposes as different specialisations were involved compared with smoke detection systems. Mr Barrett, for example, noted that gas detectors and gas analysers indicate and identify the presence of particular gases. Fires produce gaseous by-products that could be detected by gas detectors. However Mr Barrett further noted that gas detectors pass a multitude of contaminants other than smoke and would not be sensitive enough for smoke detectors.
151. Some guidance to resolve the appropriate person skilled in this field might be determined from the present application. The art, admitted in the specification to be known, deals with the problems of pollution, other than smoke, having the tendency to block filters and interfere with the proper functioning of detectors. One process described in the specification is “referencing”. In this process an air pollution transducer of an air pollution detection unit samples the air entering a protected volume and provides an offset signal to other air pollution detection units within the volume. This avoids the problem of pollution, other than smoke, that enters the volume, causing a smoke alarm signal. The specification further discusses, again as admittedly known art, a toroidal chamber arrangement for the thermo-magnetic measure of the oxygen concentration of a gas. It seems the smoke detection industry, if it were regarded a separate industry, is not devoid of drawing on the knowledge and skills of the gas detection and gas analysis industries. I favour the approach of Vision Systems. That is, the appropriate person skilled in the field is more broadly defined than asserted by Air Sense.
152. Mr Girling stated in evidence that it is inconceivable that he would have considered the detection of fires in coal pulverising mills as being relevant to monitoring atmospheres in which people are working or living. On the other hand Mr Jawerth stated that a skilled engineer faced with the problem of filter contamination in a relatively clean atmosphere where people work and live, would have asked how the problem would have been addressed in environments with higher levels of particulates where filter clogging would be much greater and more common.
153. The detection of fires in coal pulverising mills appears to be a narrow application of gas detection and gas analysis. The evidence is replete with numerous examples of fire detection systems in more hospitable and varied environments using gas detection and gas analysis. Consequently I think Mr Girling’s evidence on this point should be seen as a discussion of a particularly narrow application. In any case the present application, describing an invention of which Mr Girling was a co-inventor, clearly discusses pollution and gas measuring and monitoring arrangements as background art.
154. I regard the appropriate person skilled in this field as one skilled in the design and installation of fire detection apparatus, and being familiar with gas analysis, and gas and smoke detection techniques as means for detecting fires.
The common general knowledge
155. Vision Systems noted its evidence indicated the E700 and Olsen detector systems were sold and widely used in Australia, and brochures were distributed extensively before the priority date of the application.
156. Vision Systems submitted that extensive elements from the E700 and Olsen systems formed part of the common general knowledge before the priority date of the application. These elements related to ducting, sampling, filtering, bypass and air flow impellor arrangements.
157. AirSense appeared to accept the common general knowledge at the priority date lay in the recognition of a specific problem. That is, there was evidence of recognition of the problem of filter clogging and loss of detector sensitivity. Mr Barrett stated in evidence that, in the R&D department of IEI (Australia), he was well aware of the problem. Likewise at least Mr Cole, Mr Johnson and Mr Jawerth also understood the problem. AirSense also appeared to accept that various solutions relating to filter type, and filter and detector placement were part of the common general knowledge.
158. Under section 7(2) of the Patents Act, the relevant common general knowledge is that existing in Australia at the priority date of the application. It may appear that the common general knowledge in the fire detection industry is international in the sense that there is little or no difference in the common general knowledge between countries. Many of the companies in the industry, such as the parties in this opposition, have an international presence or sell their products internationally. On the other hand I have no clear statements before me in the evidence in this opposition that the common general knowledge in Australia at the priority date was the same as in other countries of the world. Consequently I need to treat the evidence of those declarants from the UK with a little caution in respect to statements of common general knowledge. Mr Johnson, Mr Cole, Mr Piik-Wakeling and Mr Jawerth for Vision Systems and Mr Barrett for AirSense are all relevant Australian declarants, and commented on filtering solutions to the filter clogging problem being well tried and tested.
159. I am prepared to accept the filter clogging problem was common general knowledge in Australia at the priority date of the application. Further, that changes in the type of filter used, and in the relative placement of filters and detectors, were possible solutions that were common general knowledge. I am also prepared to accept that sampling air from a main flow duct to a detector, with or without a filter upstream thereof, was common general knowledge. I regard the use of a fan or other air flow impellor device to force rapid air flow through the detector for speedy detection of smoke was also common general knowledge.
Whether There is an Inventive Step
160. The problem of frequent contamination of filters was well known at the priority date of the application. It appears significant effort was spent by personnel in the industry on finding solutions. For instance, personnel at IEI in the UK, and more relevantly in Australia, were working on filter solutions. None of these efforts appeared to satisfactorily solve the problem. As Mr Girling states, the solution inadvertently was in the gas analysis and gas detector fields. However it appears from the evidence that, before the priority date of the application, the declarants from both sides did not think to look in the gas analysis and gas detection fields in seeking a solution to the filter clogging problem.
161. It may be that Mr Girling and other declarants from both sides did not think of looking in the gas detector or gas analysis fields. On the other hand I have found earlier that, as demonstrated in Air Sense’s application itself and in Vision System’s evidence, the gas detection, gas analysis and smoke detection industries were closely allied, at least in respect to fire detection. In respect to the filter clogging problem it appears the declarants on both sides had not been as diligent in canvassing information across the gas detection, gas analysis and smoke detection industries as their evidence of their activities generally across these fields suggests. The recognition of the filter clogging problem led personnel to only consider filter-related solutions.
162. Section 7(2) of the Patents Act does not require that a person skilled in the art would have ascertained relevant information. Rather the issue is whether that person could have ascertained that information. I conclude a person skilled in the present art could have ascertained the relevant documentation from the gas analysis and gas detector fields.
163. In Gambro Pty Ltd v Fresenius Medical Care South East Asia Pty Ltd, [2004] FCA 323, Allsop J. stated at paragraph 366:
"That percolation is a well-known principle can be accepted. However, what it is usually employed for is a more relevant enquiry to assess whether it was plain or obvious to take the step of employing it to improve dialysis systems."
164. In the present case it is clear from the evidence that bypass arrangements in the form of main sampling ducts and secondary flow ducts, with the former providing a bypass of air around filter and detector units, are known in the gas detector and gas analysis fields. See specifically US Patent 4073619 and the Brown document. These documents are in the gas detection and gas analysis fields. Consequently the person skilled in the art, as determined above, could have ascertained, understood and regarded these documents as relevant.

165. As mentioned in the discussion under novelty, both of these documents disclose structures substantially identical to that of the invention as claimed in at least claims 1 and 3. The only differences are the claiming of those structures in a smoke detection system in the present application as distinct from in a waste gas analyser and in a fire detection apparatus, respectively, in the cited cases. From the Gambro (supra) case, what those arrangements are usually employed for is a more relevant enquiry to assess whether it was plain or obvious to take the step of employing them to improve smoke detection systems.
166. In both of the above documents of prior art, the bypass arrangements served a couple of purposes. In each case, the bypass of quantities of gas surplus to the requirements of the analyser was one of those uses. An evident by-product of the bypass arrangements is that less air passes through the filter and detector units leading to less frequent filter contamination.
167. I conclude the person skilled in the art, faced with the filter clogging problem, and possessing the common general knowledge and the above noted documents, would have arrived as a matter of routine at the solution claimed in claims 1 and 3 of the application. In my view, claims 1 and 3 do not have an inventive step.
168. The remaining claims define at least the additional feature of the whole stream passing through a detection module through which extends the main duct means containing the secondary duct means, the filter and the detecting means. This arrangement of items in a detection module is not disclosed in either US 4073619 or the Brown document. I also regard this arrangement as something more than a matter of routine for the person skilled in the art to arrive at.
169. I regard the remaining claims as defining an inventive step.
MANNER OF MANUFACTURE
170. At the hearing Dr Emmerson stated Vision Systems no longer pursued this ground of opposition. In the light of the Ramset Fasteners (Aust) Pty Ltd v Advanced Building Systems Pty Ltd decision, (1996) AIPC 91-226, handed down since the application's filing date, Dr Emmerson noted this ground now properly belonged under the lack of novelty and lack of inventive step grounds. I make no further finding in respect to manner of manufacture.
DECISION
171. I have found that AirSense is not disqualified from entitlement to the invention by way of association of its staff with IEI (UK), a predecessor subsidiary of Vision Systems.
172. On the other hand I have found the invention as claimed in claims 1 and 3 does not have an inventive step.
173. I have also found there is a problem with the fair basis and clarity, and consequent entitlement to the claimed priority date, of claim 5. An amendment to bring the description of the invention in line with the claim would not remedy the situation. Claim 5 is clearly flawed as it presently stands.
174. I find there is patentable subject matter in the specification. I allow sixty (60) days from the date of this decision for AirSense to claim that subject matter in the claims. If suitable amendments are not proposed within that time I will refuse the application.
COSTS
175. Both parties supported the general principle that costs follow the event.
176. Mr Hess further submitted though that the complexity of the opposition and the volume of the opponent's evidence, much of which the opponent did not ultimately rely on, should be reflected in an award of costs if AirSense was unsuccessful on any part. In that case, Mr Hess requested a further opportunity, after the decision issues, to make submissions on costs.
177. Dr Emmerson accepted it might be necessary for further submissions on costs to be made. His primary submission was that costs should follow the event.
178. I have found Vision Systems to be partly successful in this opposition on some points but not on others. I allow the parties thirty (30) days from the date of this decision to make further submissions on costs in the light of this decision.
M. G. Kraefft
Delegate of the Commissioner of Patents
Patent attorneys for the applicant : Lesicar Perrin, Adelaide
Solicitors for the opponent: : Blake Dawson Waldron, Melbourne
Patent attorneys for the opponent : Davies Collison Cave, Melbourne

[2005] APO 7

2 March 2005