A 2025: lateral flow test - our provisional answer
Two DP-tutors (Nico and Nyske) sat paper A this year as benchmarkers. When comparing our answers, it turned out that we had largely the same solution, differing only in details of the wording.We both stuck closely to the wording of the paper, and incorporated some embodiments of D1 into our (dependent) claims. D1 turned out (again) to have some useful things in it.
A claim 1 according to our solution could read something like:
1. Lateral flow test, comprising:
- a sample pad (1) for receiving a liquid sample (5),
- a conjugate pad (2), which is arranged downstream of the sample pad (1),
the conjugate pad (2) containing a detection agent (11),
the detection agent being a conjugate (11) of a first type antibody (10) and a coloured particle (9),
wherein the first type antibody (10) is adapted to specifically recognise and bind to a target
molecule (6) in the liquid sample and wherein the coloured particle has a spherical shape,
- a reaction membrane (3), which is arranged downstream of the conjugate pad (2),
which
reaction membrane (3) comprises a test line (7),
the test line (7) comprising second types antibodies (12) that are specific for the target molecule (6)
and are immobilised in a line across the surface of the membrane,
characterised in that the coloured particle is a spherical gold nanoparticle having a diameter
of 20 - 100 nm.
As will be clear from a comparison with D1, the focus of the invention are the coloured particles. D1 does not explictly mention that it's spherical, however, according to par. [008] of the client's letter, the coloured particles must have a spherical shape to ensure they move at a consistent rate. Therefore, we assumed that the blue latex particle of D1 also would have to be spherical in order for the test of D1 to work.
D1 has a lot of features in common with the invention, but the final paragraphs [014] and [015] of the client's letter move away from the blue latex particles to replace them with gold nanoparticles. D2 mentions colloidal gold , which is a solvent with gold nanoparticles in it. However, the client's letter does not mention the solvent so there is no need to put the colloidal gold in the claim.
In par. [015], the clients letter says: "We have experimented with gold nanoparticles from other manufacturers and found that any type which has a diameter of 100 nm or less is suitable for our test, since larger particles do not have the necessary red colour." We learn from this that we don't need to limit the claim specifically to the nanoparticles of the manufacturer D2. The limitation of a diameter of 100nm or less appears to be necessary in order for the invention to work. Limiting to "the necessary red colour" seems to have risk of being unclear, because what is necessary"? Par. [014] mentions "intense ruby-red" but it will be hard and even subjective to determine which red would be "intense ruby-red" and which red would not be. Because the client's letter says "necessary red colour" however, we don't have a basis for extending the gold nanoparticles to any acolour. So, having an upper limit of 100nm diameter seems to make sense.
Similar considerations apply to the lower limit of the diameter of the gold nanoparticles. Paragraph [015] tells us that "We also found that gold nanoparticles with a diameter of less than 20 nm cannot carry sufficient antibodies to give an accurate result.". Apparently, the invention does not work with nanaparticles of a smaller size.
We both included at least one claim to a kit comprising the lateral flow test according to any one of claims .. and an extraction solution for suspending a test sample.
Also, we both had a claim to the combination of a plastic cassette and the lateral flow test (or test strip thereof), either in the form of a regular dependent claim or as a claim to the plastic cassette containing the test/test strip.
We did not see any use to include a use claim or a method for ex-vivo diagnostics. Such claims would not add any further scope of protection as the product is already claimed. In addition, there were more than enough embodiments for dependent claims.
We also both decided against a separate claim for the detection agent, as the technical effect seemed to be linked to the use in the lateral flow test.
For dependent claims, we saw for example the following options:
- gold particle 40 nm diameter
- control lime + associated features
- reaction membrane of nitrocellulose + optional pore sizes
- wicking pad
- the wicking pad (4) is made from cotton, cellulose filter or glass fibre
- first type antibody = second type antibody
- the conjugate pad (2) is made from non-woven glass fibre.
- the sample pad (1) made of cellulose fibre.
- the first antibody (10) has a binding affinity having an equilibrium dissociation constant equal to or less than 10 -7M.
- the first antibody (10) and the second antibodies (12) are specific for human chorionic gonadotropin.
- the first antibody (10) and the second antibodies (12) are specific for a spike protein of SARS-CoV-2 virus.
-the conjugate pad (2) stores the detection agent (11) in dried form.
- the plastic casette is labeled to indicate a position of the test line (7) and optionally a position of a control line
- the extraction solution is a buffered solution, such as phosphate buffered saline.
Curious to hear your thoughts!
For the “brave” ones that went for an independent claim for the detection agent, would you say that it will be detrimental?
ReplyDeleteWould a claim to a gold nanoparticle + antibody detection agent conjugate lacks novelty over D2 alone? But no negative marking right? So not detrimental per se if you got the other claims!
DeleteIt would not be inventive in view of D2 which already discloses the antibody conjugate with the gold particles, and the fact that the particles used are the most commercially used
DeleteIndeed. I have essentially the same claim set as suggested above, however in a last minute 'panick' I decided to include a 15th claim for a conjugate comprising an antibody and a spherical gold nanoparticles of 20-100nm. My thought was that it was novel (selection from two lists). But I am very eager to see if I will get punished for it.....
DeleteUsually not detrimental in terms of direct deduction of points. However, you probably have this claim instead of an expected dependent claim, and therewith you miss the points that would be allocated to the expected dependent claim. But that's usually no more than a few points.
Delete2 independent claims of the same category is one of the worst things you can do in paper A imo. The past mark schemes explicitly state that they'll only mark the worst one. So that'd be your 15th claim. It's incredibly harsh
DeleteHi everyone, I would like to share my opinion regarding this aspect: what about a claim for the detection agent which disclaims the three sizes disclosed in D2? in my opinion, it would be novel (a similar solution was also present in some previous chemistry papers). Regarding the inventive step, it seems that the techical effect is related to the particular features of the conjugate... What do you think? thank you in advance for any feedback!
DeleteWould a wrongly formulated use/method claim lead to point deduction if this claim type was not expected ?
Delete"The limitation of a diameter of 100nm or less appears to be necessary in order for the invention to work".
ReplyDeleteDoes it? From the client letter, all the invention needs to work (and by work, i mean produce the technical effect of improved sensitivity) is gold particles of at least 20nm in diameter.
I don't see any statements alluding to the max diameter of 100mm being necessary for improved sensitivity. The only effect of the max diameter upper limit was that the light turns crimson read. This seems like a textbook presentation of information, thus probably wouldn't be deemed as technical according to the EPC.
I do, however, acknowledge that having a no upper limit means the claim would include colourless wavelengths (and thus the invention wouldn't work). So some form of upper limit is needed, I just don't think it should be 100nm. To get around this, I said a lower limit of 20nm, also that the diameter is configured such that the goldnanoparticle can emit light in the visible light spectrum.
Who knows!
In par. [015], the clients letter says: "We have experimented with gold nanoparticles from other manufacturers and found that any type which has a diameter of 100 nm or less is suitable for our test, since larger particles do not have the NECESSARY red colour."
DeleteThe word "necessary" seems to give a broad hint. In the past, EQE placed great emphasis on such keywords, regardless of how “useful” one would find this in real life as a patent attorney.
I agree that the EQE typically places great emphasis on statements like "essentially" and "necessary".
DeleteWhen I see these types of phrases, I tend to immediately include the gesture in a claim.
However, I had to make an exception here.
From a legal perspective, the feature deemed essential by the client has to do with the operation of the invention (i.e the invention still works as long as it's not colourless). Also, the effect being red specifically is non technical (presentation of information).
From a common sense perspective, why the examiner's intend to give us marks for excluding every colour other than red? Sometimes clients make strange demands that aren't in their best interest, and I thought this was one of them. Hoping it still gets some marks
Whops, meant to say has nothing to do. The colour being red isn't a requirement for the surprising technical effect of improved sensitivity, so for the first time ever, I ignored the clients indication of it being an essential feature.
DeleteIt is also said in D2 that, if the diameter is greater than 100 nm, the colour is transparent and then blue and black
DeleteSo I specified the 100 nm limitation because if not, the colour may be transparent and you do not have any effect
I included the range as to avoid a straightforward combination of D1 with D2 and do disable the colourless or clear problems with larger sized gold particles, and still be an inventive selection of the range 5-400nm of D2.
Deletehmm I initially drafted the same claim as yours. I also thought "Why limit to red since D1 uses other colors (blue) and it works"?
DeleteHowever, the prior art does not relate to gold nanoparticles, but to latex. So perhaps gold nanoparticles in other colors than red do not work.
Having said that, I do think your functional limitation could be right. I just decided to play safer and add the 100 nm limitation.
It would be reasonable if they accept both solutions, I would say.
What are your thoughts on a further claim to "use of the device as a pregancy test" on the grounds that pregnancy is not regarded as an illness (GL G.VI.6.1.2)?
ReplyDeleteI had the same.
DeleteI incorporated the embodiment of the pregnancy test in more structural features, i.e. in the antibody being specific for the pregnancy hormone. I thought about the use claim, but considered that a pregnancy test would take place normally in a private enviroment, so it would be of limited value in terms of scope of protection. However, looking at recent A papers, I find it hard to predict when a use claim is expected and when not.
DeleteI tied myself in knots on the nanoparticles. In the end I claimed "colour particles" with the 20-100nm diameter, then had gold nanoparticles in the early dependent claims. I'm wondering now if that makes my claim 1 insufficient.
ReplyDeleteDo you think it was clear that the control line was not needed in the independent claim? I thought long about it. D1 does say it control line is not essential as other control means can be used. There were no other control means defined in the client letter and it clearly stated their invention has the control line. I knew it wasnt essential for the test but from the wording of the clients letter, and not giving any alternative embodiments, I decided to add it to the claim.
ReplyDeleteThanks for the feed back.
That's why I put "control means" arranged to confirm validity of the test. Hope it works!
DeleteHaha ditto, included the control line, forgot the word optionally :((( first I thought that it would be synergic to achieving a high test accuracy, and no other means were presented by the client.
DeleteIt wasn’t clear to me either if the control line was essential to the lateral flow test. I debated to add it as an optional feature but ultimately I didn’t. One of the paragraphs in the client’s letter said, “advantageously, the reaction membrane also comprises a control a line…” which made me think it was required, plus a technical effect was provided that was not fully disclosed in D1. I did include an in vitro diagnostic method. According to my understanding of the relevant section of the GL on diagnostic methods, you need to compare the data to something. In the absence of the control line, you could not compare the test line to anything, which made the control line appear essential. Again, I debated having the in vitro diagnostic method only use the lateral flow test that had both the control line and test line (with a separate independent claim for the lateral flow test without the control line, and having the control line feature in a dependent claim) but then there were just too many claims. Already limiting the number of claims to 15 was challenging.
DeleteThe control line was not essential for the test line to appear, indicating the result was positive. However, it was necessary to determine whether the lateral flow test was functioning properly. Essentially, it serves as a negative control, which is particularly important when the test result is negative (no test line appears). In such cases, the absence of a test line alone does not indicate whether the result is truly negative or if the test is faulty due to expiration, damage, or malfunction. So i think a control means is essential. Delta Patent did not think so but I am still hoping :)
DeleteI agree that the control means is essential! It confirms users if the test is functioning or not. If there is no control means, it can mean 2 things: whether it is a negative/positive result based on the colored test line (valid results), or the test is invalid. Withoud the control means, we will never know whether the test is valid or invalid. Hence, I think we need to eliminate the possibility of an invalid test by adding a control means as an essential feature.
DeleteI decided against including the control line, because par. [011] of the client's letter, which describes the control line, starts with the word "advantageously". This typically is a way in which the paper indicates an embodiment for a dependent claim. I agree it's a nice to have feature, but I don't see it as an essential feature for the invention to function in the light of the problem it aims to solve - which is increased sensitivity (see par. [015])
DeleteHello Nyske and Nico,
ReplyDeleteThanks for the effort and benchmarking. I had a similar set of claims.
Some thoughts to which I would appreciate your feedback:
The only example of the lateral flow test was a strip. I am assuming the two wordings are acceptable? I claimed a lateral flow test strip.
The sample pad has to be absorbent according to the client, otherwise the invention wouldn't work. No?
The only example provided for the detection agent is in a dried form. No one knows how or if it works if it was in any other form.
Thanks!
I agree. I added something like that the conjugate is arranged in the conjugate pad so as to get rehydrated and mobilized when it comes in contact with the liquid test sample. I named my device test strip for forming a lateral floe test. In D1 or the letter it was said, that such lateral flow tests work in a way, that the lquid is moved through the test strip by capillaric force (or some other word. Had the german version). So thw wording "lateral flow test" should imply, that the luiqid is moved/movable through respective pads by capillaric force.
DeleteCheers to all
I discussed this with Nico, as he also included the strip in claim 1, because that made the claim of the embodiment with the plastic cassette easier. I think it would be acceptable. The main question is whether it would limit the scope of the claim or not and I can't really see it does.
DeleteWith respect to the sample pad, I considered adding the absorbent and the main function as described in par. [005] as a functional feature. I decided against adding main function because "even and controlled distribution" did not seem to be very clear terms. I left out the absorbent because of the word "typically" in par. [005].
I agree too, in fact D1 discloses a strip so the best promising starting point should be a strip since there are no other examples showed and it is more clear in my opinion.
DeleteI wonder about the lower limitation of 20 nm. In the German translation (not available for me anymore), I got as strict upper limitation 100 nm. However, I understood the lower limitation as optional. For exact results, more than 20mm are necessary, yet, worse results may be obtained by less than 20nm (but still results and maybe cheaper or whatever).
ReplyDeleteHave there been differences in the English and German version?
I agree with you. I assumed that the 20 nm allows a better accuracy but does not contribute to the sensivity problem. So I only specified the 100 nm limitation.
DeleteSame here. In the german text I also read the 20 nm limitation was about good results, thus less diameter would still produce a result, and the 100 nm read to be essential.
DeleteThe paper is already available on the Compendium, and I checked the German version. As I read it, it says about the same as the English version with respect to the 20 nm. I decided to put the lower limit in because I interpreted as that if there are not sufficient antibodies carried by the coloured particles, you also cannot obtain the sensitivity, if you have a very small amount of target molecule, then you need the antibodies with the coloured particles to "catch" as much of the target molecule as possible. We'll have to wait and see what the Exam Committee had in mind, I'm just taking you through what my considerations were when sitting the paper.
DeleteA general question on non-essential features in an independent claim (claim 1). I understand that marks are deducted for every non-essential feature. I, however, wonder if you still get the marks for that feature as if it was in a dependent claim?! Otherwise it feels that you get penalized twice for the same error. Any thoughts on that?
ReplyDeletesame thoughts!! does anyone know it?
DeleteIf I remember correctly, Examiner's Reports sometimes say that you still get a point or so. In principle, double penalisation is avoided.
DeleteThis comment has been removed by the author.
ReplyDeleteHow heavy is the penalty for including control line?
ReplyDeleteAnonymous
DeleteMarch 13, 2025 3:04 pm
Although "control line" was not needed, I understand control means are still necessary (control means can be e.g. a control line) - see D1: "there are some tests available
that do not include one and rely on other means to show that the test has been
performed successfully"
It's hard to say at this point in time, it will depend on how severe the Exam Committee considers the limitation to be. Normally is anywhere between 3-10 points (often around 5 or so), but it can be more.
DeleteI interpreted the "other means" as a hint to not to limit the claim at all with respect to any control means at all - the paper doesn't say that the "other means" are always incorporated in the test itself.
Unfortunately, I did not put the goldparticles in the claim. The spherical shape of the particles was Not disclosed in D1, so I thought I Get through this novelty over D1. But I see you Point with the kind of inherent disclosure. So I assume I get no points for my claim 1 Not being novel. that is quite frustrating.
ReplyDeleteI did the same as you and put spherical as distinguishing feature. I am appealing if the Examination Board considers that D1 disclosed the spherical shape of the particle - there is no way.
DeleteThe D1 figures are literally spherical though. That's already novelty destroying
DeleteHello, Yes, I might do this as well. I mean to deduce that particles in D1 are spherical without mentioning it…One could Argue that this is Kind of speculating…
DeleteWell, I also do not see a spherical particle in Fig. 1 of D1
DeleteBerliner - So does the figure of D1 disclose a 2D lateral flow, and a 2D circular particle? Or was it showing a cylinder with a circular cross-section?
DeleteIn response to "The D1 figures are literally spherical though. That's already novelty destroying".
DeleteThat is incorrect, Fig. A of F1 shows a circular (2D), shaded element 7. There is no indication of sphericity (3D). In addition, even if there was an indication of sphericity of the element 7, it would still not directly and unambigously disclose to the skilled person that the coloured particle of D1 as spherical, since it is merely a schematic drawing. see https://www.epo.org/en/legal/case-law/2022/clr_i_c_4_6.html
This comment has been removed by a blog administrator.
DeleteThe client letter already tells you that the one known in the art have spherical particles, so plus D1 showing them as spherical kinda gives it away
DeleteAaad: It's a pity you're getting so personal. I don't think that a decision in a (fictitious) examination case says anything about the skills as a European Patent Attorney in general. Besides, such decisions are not made under time pressure, as is the case in the exam.
Delete@delta Patents: Do you think you can still pass the A part if you have only given spherical indications? How much point deduction can be expected. Had the same thought.
If you have any other features in the claim that make the claim novel, you will not lose all points for claim 1. And I gave this option quite some thought as well when doing the paper, but wasn't brave enough to go for it. I wondered if the sperical would be enough of a difference, in particular in view of the drawings of D1 and hint in the paper that seemed to say it was needed. I am very curious to see the argumentation of teh Exam Committee on this point. What ultimately made me decide that it would probably not be the intended solution of the Exam Committe is that the paper puts so little emphasis on this feature and its effect. The gold nanoparticles get two full paragraphs written about them, while the spherical seems just a side remark.
DeleteI agree with you. I also consider the feature "the particles have a uniform size" essential to ensure a consistent rate. (common general knowledge?)
DeleteI work in a large UK law firm where I work under biologists and biochemists as experienced patent attorneys. I have discussed this issue in depth with them.
DeleteA figure has an illustrative purposes. It is not true to scale or detail. The latex particle could simply be shown as a circle in the drawing for practical reasons, even if it could have a different shape in reality. The text of D1 does not mention that the latex particle is spherical. Without an explicit description or reference in the text that it is a spherical particle, it cannot be concluded that the representation in the figure reflects the actual shape of the particle.
A circle in a 2D representation could also merely be the projection of a three-dimensional object. The latex particle could actually have a different shape, which is only represented as a circle in the drawing, for example as an ellipse or another geometric shape that appears as a circle from a certain angle.
If this year the examination committee does not recognise the spherical shape of the particle as a distinguishing feature over D1, that would be quite unfair according to my opinion. A previous colleague also made a good point that you can't conclude from the figure that the antibodies have a Y-shape.
You say that the client doesn't mention the colloidal/suspension part, but [0014] states that "we ordered some 40 nm colloidal cold particles...". Then [0015] states that "they" gave a great result, which refers to the colloidal gold particles the way I'm reading it...
ReplyDeleteYou also say that a use claim would not add any further scope, but I don't see how that's the case? For current technology maybe (if we assume D1 is the only relevant prior art whatsoever), but what's to say that future lateral flow test devices include all the same limitations? I definitely think that a use claim has a broader scope which is relevant to consider for the client, especially given that they explcitly state that they want to cover "other possible uses", which for me further pushes that notion.
I didn't use the colloidal because it's the particles that are functional within the invention, not the solvent. With respect to use claims, it seems a bit unpredictable when they are expected and when not (at least I haven't cracked the code for that yet!). What tipped the balance for me was that these tests are often used in a private setting. And I had more than enough embodiments to get to 15 claims, which I thought related to more useful protection.
DeleteI understand, thanks for replying! And apologies if my first post came of as a bit accusatory/rude, I wrote it quickly and didn't think too much about the phrasing.
DeleteI was agonising quite a lot over if the "colloidal" part was essential or not but came to the opposite conclusion, or rather I was scared that it would not be a working embodiment if I didn't mention it due to the statements in [0014]-[0015]. I don't know enough about chemistry to even make a guess myself as to the function of a solvent/suspension relative to the relevant particles in such a suspension.
I still think a use claim seems possible and suitable according to Guidelines G-VI-6.1.3, but I'm probably wrong since all of the benchmarkers came to the conclusion that it's not relevant to include.
How heavy would the penalty be for including
ReplyDeletewherein the coloured particle is not a gold nanoparticle with a diameter of less than 20 nm,
the lateral flow test characterized in that:
the coloured particle (9) has a spherical shape and has a diameter of 100 nm or less.
I feel the diameter was specifically related to the gold - no indication that other/all coloured particles have the same effect.
Delete@Nyske Blokhuis , I believe you are correct here as D2 discusses how the use of gold has the effect of surface plasmon resonance (or something along those lines) which provides the red/colour effect. I think this sentence was included to make it clear that the use of gold is essential.
DeleteNo kit claims?
ReplyDeleteProbably :)
DeleteWe both wrote kit-claims for the test + extraction solution
Deletehow about this one:
ReplyDelete1. A lateral flow test strip for specific detection of a target molecule (6) in a liquid sample (5),
comprising
a sample pad (1) configured to be applied with the liquid sample (5) and configured to
provide even and controlled distribution of the liquid sample (5);
a conjugate pad arranged in a downstream from the sample pad (1) to receive the liquid
sample from the sampe pad (1), wherein the conjugate contains a detection agent (11),
wherein the detection agent is a conjugate (11) of an antibody (10) and a coloured particle (9)
having a spherical shape,
wherein the antibody (10) is configured to specifically recognise and bind to the target
molecule (6); and
a reaction membrane (3) configured to receive the conjugate with bound target molecule,
wherein the reaction membrane (3) comprises a test line (7) comprising additional anitbodies
(12) that are specific for the target molecule (6) and are immobolised in a line across a surface
of the reaction membrane (3), wherein the test line is configure to indicate that the liquid
sample (5) contains the target molecule (6),
wherein the reaction membrane (3) is a nitrocellulose membrane,
characterized in that the nitrocellulose membrane (3) having pores in sizes ranging from 5
microns to less than 9 microns or from greater than 10 microns to less than 12 microns.
Maybe the range is not sufficiently far removed from the ranges of D1 such that the skilled artisan would not seriously contemplate testing it.
DeleteI agree with anonymous in the comment above. But even if you would consider the claim to be novel, then what's your argumentation for inventive step?
DeleteI fed all the information in ChatGPT, claim 1 above, disclosure of D1, and the relevant paragraph 10 of the client letter: here is the CHATGPT answer -- i know that claim would fail with the Examiner, but was just trying my luck...
DeleteChatGPT
To assess whether Claim 1 is novel and includes an inventive step, we need to analyze the differences between the claim and the prior art disclosed in the provided text.
Novelty:
The prior disclosure mentions the use of nitrocellulose membranes for lateral flow tests, stating that "the best results are obtained with a nitrocellulose membrane that has a pore size of 9-10 microns."
Claim 1 specifies that the nitrocellulose membrane has pores in sizes ranging from "5 microns to less than 9 microns or from greater than 10 microns to less than 12 microns."
The differentiation in pore size (5 microns to less than 9 microns or greater than 10 microns to less than 12 microns) compared to the prior art (9-10 microns) indicates that this claim may be novel, as it does not simply replicate the pore size disclosed.
Inventive Step:
The inventive step requires that the claimed invention is not obvious to a person skilled in the art based on the prior art.
The prior art suggests that a nitrocellulose membrane with a pore size of 9-10 microns provides the best results, but it does not suggest or imply a preference for other pore sizes, such as those specified in the claim (5 microns to less than 9 microns or greater than 10 microns to less than 12 microns).
The claim indicates that the different pore sizes may have specific advantages, such as controlling sample flow rate, which could suggest a non-obvious improvement over the previously disclosed range.
Conclusion:
Novelty: Claim 1 appears to be novel based on the differences in pore size and the specific configuration of the lateral flow test strip.
Inventive Step: Claim 1 likely includes an inventive step, as the selection of specific pore sizes outside the previously suggested range, along with the acknowledgment of their benefits in terms of sample flow control, would not be considered obvious to someone skilled in the art based on the prior disclosure.
Hi, while it is true that the description of D1 does not explictly mention that the coloures particle are spherical, FIG. A of D1 discloses somehow an spherical shape of the coloures particles (7) and given that FIG. A forms part of the disclosure of D1, it could be interpreted that D1 discloses a spherical shape of the coloures particles.
ReplyDeleteWhat do you think?
Sorry for my typos each time, "coloures" should have been "coloured" ;)
Deletehttps://www.epo.org/en/legal/case-law/2022/clr_i_c_4_6.html
DeleteDoes Fig. A directly and unambiguously disclose a spherically shaped particle? In my view, there is no way the skilled person could conclude from Fig. A ALONE that the particles of D1 have to be spherical - it's just a random circular shape - the skilled person would not derive a teachnical teaching that the coloured particles have to be limited to spherical.
I think it does.
Delete"In T 204/83 (OJ 1985, 310) the board held that features shown solely in a drawing formed part of the state of the art when a person skilled in that art was able, in the absence of any other description, to derive a technical teaching from them. ".
There's nothing unclear about the figures. There's a spherical particle seen therein. So drafting a claim to the spherical particle would lack novelty.
If not, it'd be heavily penalised on inventive step imo. Maybe -30 marks like some previous years. Ask the skilled person has to do is look at the figures in D1 to consider a spherical shape
@Anonymous thanks for your comment. Any reason you cited T 204/83 specifically, and none of the other decisions that give the opposite argument, e.g. T 896/92 or T 2052/14?
DeleteThe skilled person of the invention sees a circular, shaded geometric element identified as a particle. The idea that the skilled person would directly and unambiguously derive from Fig. A (without any hint in the description) a technical teaching that the blue latex particle of D1 is necessarily spherical seems fantastical to me.
There are only two 3 dimensional shapes which have a circular cross-section in 2D, a sphere, and a rod. Since D1 did not disclose a rod the only possible reason why there would be a circular cross-section is because the particle is a sphere!
DeleteThe client letter indeed said, that a spherical shape is a must for the luiquid to flow equally through the pad/strip. But it was nowhere said, that such an equal flow is a must? I interpreted it, that an equal flow is an optional benefit. Therefore i delted "spherical" from my preamble and put it in the characterizing portion in front of the gold nanoparticles... As D1 and the client letter nowhere disclosed, that blue latex particles are spheric.
Delete@Aaad "there are only two 3D shapes which have a circular cross-section 2D.
DeleteLook on your desk - you may find a number, possibly dozens, of different types of pens, each having a circular cross-section and a distinctive 3D shape.
I agree that the particles in D1 appear to have a sphere shape. However, considering that the shape of the antibodies in the same figure is schematical, I don't think it is directly and unambiguously derivable from D1 that the particles are spherical.
DeleteThanks for sharing your answers.
ReplyDeleteI also think a detection agent in itself would not have been novel, as these were disclosed by D2 (which teaches that antibodies may be conjugated to gold particles in the last paragraph=detection agent).
I did not claim a control line, but "means to confirm that the liquid sample containing the conjugates/detecting agent successfully reached the test line and had a chance to interact with it", as I guessed the control line could be generalised based on D1.
I had a manufacturing method of a lateral strip test, which, as an afterthought, I regret limiting to the lateral strip tests of the product claims, as it could have offered broader protection to the use of the detection agent if not referring to the products (kind of equivalent to a use claim for the detection agent in lateral flow tests).
I agree that the diagnostic uses are kind of implied by the selection of the antibodies, by I still felt use claims were needed (methods of detecting a target molecules with the lateral strip tests) as I read these as required by [002] of the client letter. A53(c) should not be a problem, as the sample is not returned to the human body (GL, G-II, 4.2.1, "Treatment of body tissues or fluids after they have been removed from the human or animal body, or diagnostic methods applied thereon, are not excluded from patentability as long as these tissues or fluids are not returned to the same body. ").
I did not specify the materials of the several pads/membranes, as these were all known from D1 (at least the ones having desirable effects).
I added a dependent claim to specify 99+% sphericity, as I am concerned about the clarity of "spherical".
I did not specify the 20 nm lower limitation because it was written (in French) that all particles having a diameter lower than 100 nm works, and that it improves sensitivity.
ReplyDeleteRegarding the 20 nm, it was written that it allowed a better accuracy, which I considered as a different technical effect than the sensitivity.
Hence, I specified the 20 nm only in a dependent claim.
I had both the upper and lower limits in the immediate dependent claims as it is clear as day that these limits do not contribute to the inventive step over D2.
DeleteYou do not have an effect without the 100 nm limitation : the particle may be colourless if the diameter is over 100 nm
DeleteI just looked up the French version, and google translate translates it into the same as the English version: "We also found that gold nanoparticles with a diameter of less than 20 nm cannot carry sufficient antibodies to give an accurate result.". I took that to mean that for less than 20nm the results are not reliable, false negatives, so that range (<20) is not enabled?
Delete@Unfortunate, it was clearly stated by the client that above 20nm is required for the functioning of the invention (the English version mentioned that accuracy was not good enough below this point) and the 'red line' was very clearly 'necessary' to the client and, as per D2, the only way to achieve this was by having a diameter of less than 100nm.
DeleteAs for inventive step, D2 ascribed no technical effect to the 20nm diameter so it would not be clear to the skilled person that including a 20nm limit on the diameter would have the technical effect of 'improving accuracy' (or something like that).
@Joel I understand your point regarding the 20 nm limitation and I hesitated a lot as to put it in claim 1 or not.
DeleteI decided not to because I assumed that, yes, under 20 nm it wouldn’t be accurate but it is still more sensitive than latex. I focused on the sensitivity problem and the 20 nm does not solve it. I did that because there were some previous A papers wherein a feature was said to be indispensable but it was not expected in claim 1 because it did not solve the main technical problem. I assumed that the epo used two different words (sensitivity vs accuracy) to show that the 20 nm limitation is not about sensitivity and thus is not expected in claim 1.
Anyway, it is difficult to know what are the expectations !
> "D1 does not explictly mention that it's spherical"
ReplyDeleteI agree - it is not mentioned in the text of D1 and the schematic drawing in Fig. A is too generic to allow the skilled person to derive a technical teaching from it.
> "however, according to par. [00] of the client's letter, the coloured particles must have a spherical shape to ensure they move at a consistent rate. Therefore, we assumed that the blue latex particle of D1 also would have to be spherical in order for the test of D1 to work."
Seems like a massive overreach - in particular considering how limiting and specific a "spherical" particle is and how nothing suggests this sentence from the client's letter is applicable to D1 (D1 doesn't mention the need for a consistent rate movement, for example).
I agree. I don't see why a consistent rate movement would be essential. It could well be that an inconsistent rate results in a longer time to yield the result for example, but is not essential for the test to be carried out.
DeleteIn addition, I took the following sentence as proof that the nanoparticles do not need to be spherical, since they said that any type can be used:
We have experimented with gold nanoparticles from other
manufacturers and found that any type which has a diameter of 100 nm or less is
suitable for our test
I also didn’t include sphericity because consistent rate of movement was not disclosed as an advantage or disadvantage for achieving the result. I don’t think it is essential. I added however that the first type of antibodies is bound to the coloured particle to make sure that the particles are carried to the reaction membrane
DeleteI see your points, now I’m doubting if I should have put spherical in my claim 1….
DeleteBut in D2, the nano particles are shown to have a shpericity of 99%+ right? So surely a limitation to spherical isn’t that limiting in practice?
Or maybe another supplier can produce cubic nano particles that work as well????
I agree with you.
DeleteI agree with you. I also consider that "the particles have a uniform size" essential (according to common general knowledge) to ensure a consistent rate. This consistent rate is advantageous because it facilitates the development of a colored test line.
DeleteIt seems "(...) test line (7), the test line (7) comprising (...) immobilised in a line across the surface of the membrane," has clarity problems. I wrote "immobilised in the test line", if I understood correctly.
ReplyDeleteMany thanks for the feedback and your comments as well as proposed claim 1. As paper A itself should be managable without having additional technical knowledge, I´m wondering if in this case a limitation of the target molecule being a protein would establish novelty over D1, since D1 is only talking about hCG which is a hormone. However, hormones generally encompass small molecules, peptides, proteins etc. I didn´t saw that hormone or hCG was explained in detail and I was not sure if hCG is a small molecule, a peptide or a protein or any other possible substance of this class. Meanwhile I was checking it and some sources provide information that hCG is a peptide others that hCG is a glyoprotein. What do you think?
ReplyDeleteI also included proteins in claim 1 instead of antibody for the same reason
DeleteI also thought long and hard on how to generalise antibodies, because in D2 also nucleic acids can be targeted. So the entire field of detection arrays of DNA mutations etc might be thus claimable. But this required specific Biotech knowledge and decided not to use expert knowledge… in hindsight, it would have been an awesome claim, because it would have covered polymerase chain reactions, sequencing primers, markers, and other Biotech related things primers etc. The effect would require tho complicated thermal protocols so I dropped it
DeleteI have a background in mechanics and materials, so I didn't think about this at all to be honest. Maybe limiting to proteins would make the claim novel, but how would you then argue inventive step just by what is given in the paper?
DeleteAt some point I needed to make a decision because I spent a lot of time thinking for a suitable distinguishing feature with a technical effect while not excluding working embodiments. The gold nanoparticle option seemed good, but for this limitation the working embodiment with latex particles would be excluded which also provide a detection possibility, just with less sensitivity (as far as I remember, working embodiments should not be exluded). In addition, by combinig D1+D2 for inventive step the gold nanoparticles with the range 20-100nm would be somehow obvious (arguments could be presented for and against obviousness, but I didn‘t want to risk loosing 70-80% of marks for lack of inventiveness), because the well working gold nanoparticles from D2 have diameters falling in the range of 20-100. However, at end I decided to go with the option that the antibodies at the testline specifically bind proteins (to cover at least spike-proteins mentioned by the client several times as well as other possible target proteins and also to cover latex and gold particles ; limiting to spike-protein seemed a bit too much) as neither D1 nor D2 mention that antibodies at the testline can bind proteins. For inventive step, the argument would be not obvious from D1 and D2 as neither of both documents mention antibodies at the test line that specifically bind proteins (its not a strong argument of course). It was somehow a decision what exclusion would be less painful, either working embodiments with latex particles or that the test cannot be used for pregnancy detection purpose and I decided not to exclude working embodiments.
DeleteI did not use the term « nanoparticle » since I considered it obvious given the diameter of less than 100 nm.
ReplyDeleteI came to the exact same solution but made a critical mistake at the end. I assumed it was too easy and looked for something I might have overlooked. Near the end, I noticed that the client mentioned the effect only in tests with the SARS virus. Based on this, I concluded - against the client’s wishes - that it was necessary to restrict it to that virus.
ReplyDeleteI'm sure that will cost all the points..
I think that would be merely an unnecessary limitation.
DeleteI am of the view that the control line is an essential element of a sufficient lateral flow test. D1 merely discloses that other *pregnancy tests* in general do not include one and rely on other means to show that the test has been performed successfully, however the client's letter makes it clear that the control line is important to prove the test has functioned properly and provides no other pointer to a different control means. Without any control means, a result of a given lateral flow test is unreliable. I also believe the inventive step argument is weakened if the test is not accurate (where is the benefit of a more sensitive test that is inaccurate). However, I appreciate that, at its core, the creation of a line at the test line is all that is required conceptually. So it depends whether the examiners want a claim 1 narrowed around the conceptual inventive concept per se, or a claim to a lateral flow test which is sufficient. Perhaps the exercise was in the first and not the latter. However, I hope it is the latter.
ReplyDeleteI agree that a control means need to be in claim 1 to show that the test has been carried out correctly. Then, I specified a control line as an example of the control means in the dependent claim. D1 only mentioned that control line is optional, and other means can be used to show that the test has been carried out correctly. Without a control means, there is no way to have a reliable information whether the test is carried out correctly or not.
Deletecontrol means could also just be another test... or something else independant of the flow test
Deletei agree. paper D sucked :D
DeleteI am in an unfortunate situation. I did not include the diameter range values in claim 1. I had it initially in the independent claim. Then I went after comparison of all the features against the prior art references D1 and D2. I found out that characterizing the gold nanoparticles with the spherical shape provided both novelty and sufficient inventive step arguments against D1 and D2. Note that D2 discloses specific examples which disclose the claimed numerical range for the diameter. Thus, it is a clarity issue. Not clear how many points am I losing for not having the numerical range in claim 1 itself.
ReplyDeleteIs it not important to state in claim 1 that conjugate pad is arranged such that when the liquid sample reaches the conjugate pad, the liquid sample can rehydrate and mobilise the detection agent conjugate? In my opinion for the test to work, it is essential that the detection agent conjugate is able to mobilise towards the reaction membrane.
ReplyDeleteI also added this feature
DeleteI had similiar specifications too. They should be in contrast to the immobilised antidodies in the reaction membrane.
DeleteI thought about this as well, but I struggled to find the words in the paper that would go nicely into a claim for that. When I tried got awfully complicated. But maybe that's just me ;-)
DeleteIt is opitional that detection agent is in dried state, so rehydrate is optional too, but mobilise seems to be imporatant, i also havent included though...
DeleteThanks for the solution Deltapatents!
ReplyDeleteI do think a method of detecting a target molecule would be relevant, as most dependent product claims were known and had no technical effect. So they are not really good fallback positions.
Regarding your comment "We did not see any use to include a use claim or a method for ex-vivo diagnostics. Such claims would not add any further scope of protection as the product is already claimed", isn't it the case for all such use/method claims?
Even though protection for use/methods are more limited, they are not useless and are often expected in the recent papers. Finally, it would be easier to define the the target (spike protein, etc) and the liquid sample (saliva, blood, etc) in the method claim.
What do you think? Thanks for any feedback from any one here.
i agree, and i wrote it. Also in the light of last years test, where product and use had to be separated and so i made sure to not include saliva etc in product claim but in process claim.
DeleteI still find it a bit unpredictable when use claims are expected or not. We'll see when the Examiner's Report comes out
DeleteBut what is the logic behind completely eliminating the colored latex particles? It's like killing one complete embodiment from the disclosure.
ReplyDeleteD1 discloses (blue)-colored latex particles.
DeleteDear Nyske, could you please elaborate on the structural details that are required to guarantee an effective testing in capillary flow? Downstream seems unclear to me and all elements should follow in a particular order, sample ~ takes conjugate ~ moves to test line and reacts, moves further to control line. It would be essential that the sample pad is in fluidic contact with the conjugate pad which in turn with the reaction membrane. Do you regard them as implicit in “lateral flow test device”?
ReplyDeleteI also generalised to any test device based on capillary flow, not just lateral flow test devices, thereby including circles or vertical flow devices which might flow by gravity towards the test strip. Then of course I had to specify that the elements are arranged such as to enable capillary flow in a particular order (e.g control being behind of test line). But then of course I included the control line … :(
In dependent claims I specified proteins, spike proteins of viruses, hormones (to enter field of D1)
I was thinking about the capillary flow, order of f elelemts etc as well, but didn't find to much helpful wording in the paper, so I ussuemed the "downstream" would be enough. My claim just got overly complicated when I tried to put more in, and let me to a direction where I had to "invent" a lot of wording myself. I though that would not have been the intention of the drafters of the paper.
DeleteMy product claim is very similar yey, but what about the method claim? I also wrote method claim.
ReplyDeleteI have done more or less the same with 2 differences:
ReplyDelete- I have defined the sample pad using the functional language used by the client (simply writing a sample pad (1) for receiving a liquid sample (5) misses the properties that the client highlights as important for the sample pad to work)
- I have limited claim 1 to include the wiking pad made of an absorbent material (while the client letter mention that this is "helpful" and thus appears not to be prima facie essential, it was clear that the wicking pad was pretty important for the sensitivity of the test. As the problem to be solved is in my opinion the provision of a test with improved sensitivity, it was suddenly necessary to have all the parts that are important to the sensitivity. Else one could argue that the inventive step was not enabled over the whole scope of the claim. Is a pregnacy test with gold particle (20-100) but no wicking pad better than a pregancy test with the latex-particle and a wicking pad? In view of the effect described by the client, it would be difficult to argue without further tests. Further, D2 already disclosed the antigen-conjugate, preferred embodiment were 20, 40, 100 nm, and that these particles are colored. So I came to the conclusion that to achieve an inventive improvement anything that was important for the sensitivity should be included. Ultimately, faced with the choice between missing an essential feature for achieving inventive step, and an undue limitation, I preferred risking losing some points due to the limitation.)
Overall the rest look the same, so I think I should not be too worried in case I was wrong.
Well put, I agree with you 100% :-)
DeleteI included the wicking pad in claim 1 for exactly the same reason. In hindsight, I wonder if it would have been obvious for the skilled person to select the range of 20-100 nm, and in particular the lower limit of 20 nm, if D2 sells a range of 0.5 to 400 nm, and does not hint to a particular range being preferred in the generic reference that the gold nanoparticles are suitable for conjugation. A non-obvious alternative could still achieve an inventive step, albeit the enhanced sensitivity provides a stronger inventive step argument.
DeleteI also agree that the wicking pad was required for increased sensitivity of the overall test to remove the excess
DeleteI agree 100% with your point re. wicking pad. That was also my train of thoughts when I decided to put it in claim 1.
DeleteVery interesting! I thought about including the wicking pad too, in fact I still have an instance of “the wicking pad” somewhere in the claim, forgotten it when moving the pad then to depclaim 6.
DeleteI deemed that the 10-fold increase in sensitivity was enough over D1, which can be further improved by the wicked pad, as a fallback. The control line is in tho…should have formulated with “and optionally a control line”, but in the end deemed it as essential.
Furthermore, the client's letter indicated "we find it helpful also to include a wicking pad (4)...". In my view, the term "helpful" does not clearly and unambiguously make it optional. Considering the gist of the advantageous technical effect of the invention, which is to improve sensitivity, it should be interpreted otherwise instead.
DeleteRegarding your point #1 re. specifying the sample pad, imo it is not needed and I agree with Deltapatents' solution as is, the even and controlled distribution is rather a result to be achieved in my view.
DeleteDid anyone else opt to remove the "detecting agent" part of the claim? I.e. just stating that the conjugate pad comprises a conjugate with an antibody and a colouring agent.
ReplyDeleteIt was the very last thing I did, in hindsight and in view of the suggestion here that feels so-so, but I thought that it added some potential unclarity with respect to the reference numerals (both agent and conjugate being 11), but mostly I thought that nothing relevant was lost when removing it... I kept it in the description though as a fallback position just in case (which may have excarerbated the possible error on second thought since it arguably makes my claim inconsistent with the description).
I also skipped in entirely, and just referred to "a conjugate (11) of an antibody (10) and a coloured particle (9)" throughout the claims and description. As you said, the term "detection agent" did not seem necessary, not bring other benefits to the clarity of the claim.
DeleteI agree. Did the same. At least it should be implicit from D1, that a conjugate is an antibody and a colouring agent and that it works as a detecting agent.
Deletei think that would not make much of a difference, in scope of the claim. So I expect it to be OK
Deletethe detecting agent IS the conjugate. They had the even the same reference number. There is absolutely no difference.
DeleteHello, dear Nico and Nyske, thank you for the solution:-).
ReplyDeleteI had a similar claim 1 as yours, please see below.
I have a question with the word "gold" for the "nanoparticles". In D2 §001 the "gold nanoparticles" are described as being extremely uniform spherical particles with a narrow size-distribution range". My claim 1 for the "coloured particles" is "coloured particles (9) have a spherical shape, and are nanoparticles having a diameter of 100 nm or less and not less than 20 nm" where I did not use "gold" for nanoparticles. Becasue it appears that the difference between "using gold" and "without using gold" is whether the particles are "uniform" or not. Since the "uniform" is a preferred embodiment as described in the client letter (forgot where it mentions), I leave out the word "gold" but remains the "spherical shape" and "nanoparticles from 100 to 20 nm".
I am not sure whether my analysis is reasonable and would like to ask your opinion.
Another thing is I claimed for a test strip for lateral flow tests. Do you think this is also an acceptable wording?
For sample pad (1) and the arrangement of the 3 elements, I think I have clarity issues.
1. A test strip for lateral flow tests, the strip comprises
a sample pad (1) that provides even and controlled distribution of a liquid sample to be
tested,
a conjugate pad (2) that stores detection agents (11) for the test,
a reaction membrane (3) having a test line (7) comprising additional antibodies (12) that are
specific for a target molecule (6) in the liquid sample and are immobilised in a line across the
surface of the membrane (3)
wherein
the detection agent is a conjugate (11) of an antibody (10) and a coloured particle (9) in
which the antibodies(10) are attached coloured particles (9),
the antibody (10) is able to specifically recognise and bind to the target molecule (6) in the
liquid sample,
the coloured particles (9) have a spherical shape, and are nanoparticles having a diameter of
100 nm or less and not less than 20 nm, and
the sample pad (1), the conjugate pad (2), reaction membrane (3) are arranged in the direction
of the capillary flow of the liquid.
I decided to stick to the gold because of the technical effect of the colour. And I decided not to include the uniformity because par. [015] says that they also used gold nanoparticles of other manufacturere and that those worked too.
DeleteDear Nyske Blokhuis, thank you very much for your reply.
DeleteHow about when considering both of the following information?
D2§001 describes that "Our gold nanoparticles have been developed using specialised
techniques that enable the production of extremely "uniform" "spherical particles" with a
"narrow size-distribution range"."
D2§002 describes that "Gold nanoparticles absorb and scatter light resulting in colours ranging from vibrant reds ("spherical particles" that "have a diameter of 100 nm or less") to blues to black and finally to clear and colourless." Especially here in the bracket of D2§002, only the "spherical particles" and "the size 100 nm or less" are mentioned both essential to the red colour, "uniform" is not mentioned.
So the question is whether "uniform" is also essential for the colour to be novel over D1.
The effect of "uniform" appears only relevant to the "uniform velocity" but in combination with "spherical" (see §8 of the client letter: These particles are "typically" approximately the same size and "must" be spherical in shape to move at a uniform velocity".)
Further D1 describe "small, blue-coloured latex particles (7)" not mentioning whether it is uniform or not.
I did not find any clue that explicitly describes "uniform" is also essential to the colour. do you find it anywhere?
If uniform is also essential to the colour, then the wording in bracket of D2§002 must include "uniform", correct?
Looking forward to hearing from your opinion. I am afraid of the novelty issue over D1.
Many thanks!
So the "uniform" is confirmed by the clients letter not relevant or essential to the red colour.
How do you think?
How much penalisation do you think will be applied for further including in the independent claim:
ReplyDelete1) That the antibody has a binding affinity having an equilibrium dissociation constant equal to or less than 10 -7M? Because the letter says that "Ideally, the antibody should have a high affinity", it seems essential, and "high" being unclear, the only option is to include the parameter that defines what "high" means?
2) That the reaction membrane is made of nitrocellulose with the minimum pore size of 5microns? Because according to the letter it seemed essential to allow fixing the antibodies and using the pore size to control the flow?
In summary, why do you consider that features 1) and 2) are not essential, and if so, how much points will be subtracted for such unnecessary limitations?
Thank you!
I had the same thought for point 1 mentioned
Delete1. the “ideally” seems to be a hint that it does not have to be absolutely fulfilled. 2. I kind of remember that nitrocellulose is an example? The pore size is only mentioned for this example type
DeleteUsually they take away 5-7marks per unnecessary limitation right? So if the main claim is 40 marks, you’ll get 26-30??
DeleteIt may be more than 40, since use claim seemed innapropriate
I considered these to be dependent claims, as they did not seem absolutely necessary for the invention to work. The number of points to be deducted for what the Exam Committee deems to be unnecessary limitations varies - in recent years we've seen anything from 3 to -exceptioanlly- 30 (!) points. We'll just have to see when the Examiner's Report comes out.
DeleteHi Nyske, thank you for providing us your solution! Appreciate it.
ReplyDeleteI have a question regarding your statement wherein you think that use claim is not needed, and that it is covered by the dependent claim specifying the antibodies.
In your solution, the antibodies are specified only as hCG and SARS-CoV-2.
However, the client explicitly mentioned in par [001] and [002] that:
[001] "the demand for these tests has decreased and so we are looking into other markets for our products.";
[002] "Lateral flow tests can be used to diagnose infections caused by bacteria and viruses other than SARS-CoV-2, and are also used for home pregnancy tests. We would like to protect the latest developments of our technology with a new patent application that covers testing for COVID-19 along with other possible uses."
isn't it a strong indication to include possibility to test/diagnose other viruses than SARS-CoV-2? Furthermore, does the explicit wish of the client regarding "covers ... with other possible uses" not mean they want use claim(s) for each possible diagnosis?
Thanks for your answer!
I think so too, i wrote method, the steps for method were in D1..
DeleteClaim 12:
Method of detecting target molecule (6) in liquid sample (5), comprising:
-providing lateral flow test according to any of the previous claims
collecting a liquid sample (5) on a sample pad (1);
-drawing a liquid sample along the lateral flow test using capillary flow to the conjugate
pad (2), which contains a detection agent (11), wherein, if the target molecule (6) is
present in the liquid sample (5), it binds to the antibody part (10) of the detection agent
(11) ;
-the detection agent (11) with bound target molecule (6) flowing downstream to the
reaction membrane (3);
-when detection agent (11) with bound target molecule (6) reaches the test line
(7), detection agent (11) with bound target molecule reacts with second antibodies (12),
leading to a visible change, indicating a positive test.
Claim 13
Method of detecting target molecule (6) in liquid sample (5) according to claim 12, wherein the liquid sample (5) comprises urine or blood or saliva or, a nosal or throat swab sample that has been suspended in an extraction solution.
Claim 14
Method of detecting target molecule (6) in liquid sample (5) according to claim 12, wherein the target molecule (6) being detected is hCG hormone or the spike protein from the virus, especially SARS-CoV-2 virus.
Claim 15
Method of detecting target molecule (6) in liquid sample (5) according to claim 12, wherein
when the liquid sample (5) reaches the conjugate pad (2), it rehydrates and mobilises the
detection agent (11).
My claim 1 was not limited to any specific target molecule, so I think I covered the desired broadness there.
DeleteDear Nico and Nyske, thank you for drafting the claim.
ReplyDeleteI was wondering how limiting would it be to limiting the first antibody to binding affinity having an equilibrium dissociation constant equal to or less than 10 -7M as it was mentioned, otherwise it wouldn't be specific enaough. It seems like I am the only one limit it to it :-)
Thank you!
I have that limitation too in the main claim, but regret it afterwards, so I am also “curious” to get to know how much it could/will be penalized.
Delete@Anonymous, the binding affinity seemed to be the same in the client's letter and D1 but the limitation of 'equal or less' may be viewed harshly by the examiners as it means a workaround could be to include an anti-body with a slightly higher affinity, which would probably still function correctly but not infringe. But, I'm not an examiner, so I may be wrong!
DeleteThere are always more candidates who had the same thing! I think it's an unncessary limitation, but not a very severe one.
DeleteBon, j'ai une solution similaire. Deux différences : je dis que l'anticorps est spécifique à la molécule, simplement. Ce qui pourrait ne pas être clair à la réflexion... Et je dis que le tampon échantillon est fait en matériau absorbant. Quand le client dit que le tampon échantillon est important et doit jouer le rôle d'une éponge, je pensais que ça impliquait que c'était une caractéristique essentielle. Bon, on verra...
ReplyDeleteAh et puis, je n'ai pas mis dans la partie caractérisante que les particules d'or sont sphériques (puisqu'on dit déjà dans le préambule que les particules colorées sont sphériques). Et j'ai mis que c'était de l'or colloïdal, parce que j'ai recopié le client. Bon.
DeleteI am going to take screenshot of this answer :)
ReplyDeleteDid nobody add any statement about the reaction membrane (3) having a pore size of at least 5 microns" into the main claim? Do you know how many points I lose due to this limitation?
ReplyDelete@ Elif, too hard to tell at this stage, the feature did seem 'useful' so probably no more than a 10 mark deduction (considering deductions in past papers).
DeleteThe wicking pad is mentioned by the client as helpful. The client finds that the wicking pad increases sensitivity + the working principle how this effect is achieved by providing a wicking pad. D1 discloses a wicking pad (or a wick) but only briefly mentioned that it absorbs the excess liquid sample. D1 is silent about the wick having a technical effect of increasing sensitivity.
ReplyDeleteNowhere in D1, as well as the client’s letter, it is mentioned that the wick can be left out from the test (Unlike the control line, wherein D1 explicitly explains that it can be replaced by other means).
In my view, the wicking pad is therefore essential for claim 1.
Same here. And if they though it was not essential, I hope they will deduct max 8 points, not like -15 or something
DeleteHelpful, yes, but not essential. It's not essential for the detection, in that you'd still get the technical effect of the gold nanoparticles (with the size restrictions) without the wicking pad. Yes it may increase sensitivity but this is separate to the sensitivity increase of the gold. The hint was that it was present in the prior art.
DeleteAnother benchmarker here - I essentially had the same answer as Nico and Nyske, with some very minor differences (such as defining the downstream direction in claim 1). I also included a kit claim (lateral flow test plus solution), and did not include a method of use claim.
ReplyDeleteWhat was your reasoning for not including a use claim of the (colloidal) gold particles?
DeleteMy claim 1 also looks very similar. Concerning the question by Erik Olsson: I had a brief thought of writing a claim "use of the later flow test strip for diagnosis/detection of an infection/pregnancy" - but then you get into Art. 53(c) EPC exclusion territory.
DeleteI wrote a method claim, in which I integrated the solution as optional, but made sure that the method is only for detecting the target molecule, not diagnosing anything. In the last few minutes, I noticed that a kit claim would have been nice as well, but I then only wrote it as addition into the description part due to time restrictions.
i thought that since the liquid sample is not returned to body, claiming diagnostic method is possible...
DeleteThanks for the reply. I realize that I'm most likely incorrect since none of the benchmarkers have done something similar, but I still don't understand why a use claim would not be possible and/or suitable? I understand that a method for diagnosis runs into 53(c) territory, but I thought it would be possible with a claim reading something like "A composition comprising a suspension of gold nanoparticles with a diameter of 20 - 100 nm in a solvent, for use in a lateral flow diagnosis method". I think the guidelines on medical use claims for diagnosis seem to indicate that it would be patentable - https://www.epo.org/en/legal/guidelines-epc/2024/g_vi_6_1_3.html, since it is both novel and surprising to use the gold particles with the 20-100 nm limitation in such a method...
DeleteIn EPO GL 2024 G-VI 6.1.3, it is written how we can formulate a use claim for diagnosis. I thought this was the direction of the paper.
DeleteQuoted from said GL:
“Claim 1 could be reformulated as "Use of [...] in the "in vitro/ex vivo" diagnosis of disease Y". If the application as filed discloses, either explicitly or implicitly, that the claimed diagnostic methods are to be carried out "in vivo", the wording of claim 1 could also be limited to encompass only "in vivo" methods, as described above.”
@Erik and Anonymous: I believe A53(c) should not be an issue for the present case, in view, inter alia, of this passage of the guidelines:
DeleteGL, G-II, 4.2.1, "Treatment of body tissues or fluids after they have been removed from the human or animal body, or diagnostic methods applied thereon, are not excluded from patentability as long as these tissues or fluids are not returned to the same body. ".
Yes, to take a sample (of whatever nature) you need to interact with the human/animal body, but after the test, the sample remains on the strip, is not returned to the body. So, A53(c), in my opinion, should not be an issue, even if a diagnosis is reached at the end of the test, and, consequently, claims in an A54(4)/(5) format should not be allowed (or better, would read on the composition as such, suitable for the recited use).
@GB - I think the statement as quoted supports your conclusion, but it gives me some pause that the passage from which it is taken refers to dead bodies... even though it does seem like the part about blood banks is to be a standalone statement. However, the following passage refers explicitly to tests carried out "on or in relation to" the living human or animal body, which more limiting language.
DeleteFurther, the specific diagnostic part of that section, i.e. 4.2.1.3 goes into more detail about this, and states that:
"In order to determine whether a method step of a technical nature fulfils the criterion "practised on the human or animal body" it must be ascertained whether an interaction with the human or animal body takes place. The type or intensity of the interaction is not decisive: this criterion is fulfilled if the performance of the method step in question necessitates the presence of the body. Direct physical contact with the body is not required."
Based on this, my conclusion is that a method of diagnosis would be excluded under 53(c), at least with respect to COVID and other diseases.
@Erik, Thanks for your reply. Here is the full passage of the GL (I added three markers, I, II, and III:
Delete"[I] To be excluded from patentability, a treatment or diagnostic method must actually be carried out on the living human or animal body (G 1/04). [II] A treatment of or diagnostic method practised on a dead human or animal body would therefore not be excluded from patentability by virtue of Art. 53(c). [IIIA] Treatment of body tissues or fluids after they have been removed from the human or animal body, or diagnostic methods applied thereon, are not excluded from patentability as long as these tissues or fluids are not returned to the same body. [IIIB] Thus the treatment of blood for storage in a blood bank or diagnostic testing of blood samples is not excluded, whereas a treatment of blood by dialysis with the blood being returned to the same body would be excluded."
In my view, there is first a general statement (I), and then two specific and separate cases (II and III) discussed.
If dealing with a dead body (II), A53(c) doesn't apply, period, whatever you do to the dead body, its parts, etc.
If dealing with a living body (III), you may take samples, as long as the sample is not returned to the living body (IIIA), hence the reference to dialysis [not allowed, treatment] vs. simple diagnostic blood test in IIIB.
I agree that taking certain samples could run into troubles with the exclusion for surgical methods (and maybe specifying the type of samples to "routine" ones such as saliva, blood, nose swab, etc., should have been considered), but should not run into trouble with exclusion for diagnostic methods.
With respect to 4.2.1.3, my understanding is that the examination phase is defined as including the collection of data. In this case, the "data" (= visual observation of the test line) are collected while not interacting with the living body, so the exclusion of diagnostic methods should still not apply. But I am curious to see what the Committee will say (if use claims, and in which format, were needed at all...)
@GB - I basically agree with your interpretation of the quoted passage, the issue is the contradictory statements in the following passage as well as in 4.2.1.3 in my view... In our test we need to extract something from the human body which we want to test, e.g. saliva, blood, or similar, which as far as I understand is the "data collection" step (i.e. not the observation, that would be steps ii-iv). This extraction definitely "necessitates the presence of the body" as stated in 4.2.1.3 in how I understand it, since we can't take a sample from a body without that particular body being "present".
Delete@ Erik - I guess it really boils down as to how the steps are matched then, if you include sample collection in the data collection or not. From my understanding, for a later flow test, the match is:
Deletei. data collection - run the test on a sample to (possibly) generate the test line;
ii. comparison with standard - take the test near the instruction leaflet to know (or mentally refer to) an image showing that the test line indicates presence of the target and absence of test line indicates target is not present;
iii. determine a deviation from standard - conclude that the test line is actually present, hence the target molecule is present, deviating from healthy standard of no test line;
iv. decision phase - as the target is present, the subject has (COVID/condition being tested).
With the above division, there is no contradiction between the two passages of the guidelines, as the sample is simply used but is not extracted during the data collection step (=placing the sample on the test), so blood tests/lateral flow tests are not excluded from patentability. It would also make no difference if the sample is freshly collected or has been sitting in a fridge for a week. It is only when the sample is placed on the test that data to compare with a standard are generated, hence the first step is performed.
If I understand your point, you include the extraction of the sample in the examination phase - then there would be a contradiction between the two passages of the guidelines, but this would also lead to a complete exclusion of any diagnostic method - an interaction of any kind with the body of the subject need to happen at a certain point in time, otherwise no diagnosis for that specific subject would ever be possible.
Hi Nyske, I wrote the colour particle comprising a gold nanoparticle… instead of IS a gold particle. Will there be any deduction on this? Since comprising is broader than “is” as such…
DeleteIf your use claim is “Use of a product according to any one of the preceding claims for testing pregnacy”, it does not expand the scope of protection as the product is already claimed as such and hence includes any use thereof. It would just give fallback in case the product is already known but not for use as a pragnacy test - G2/88 -
Delete@Roel - I realize that such a claim is more narrow and that there is no use (pun intended) for it, but what do you think about my suggestion of a use claim for colloidal gold nanoparticles with 20-100 nm in a lateral flow diagnosis method? I still haven't understood why such a claim would not be suitable or desirable, and it is (if allowable) certainly broader than the scope of the product claim itself.
DeleteWhat do you think about limiting "lateral test for detecting a spike protein". Do you think it may be considered as "suitable for" and not be penalized like -30?
ReplyDeleteI have basically a similar claim, only I did say that the detection agent is for detecting a target molecule....
ReplyDeleteI also added a kit claim. Furthermore in the description I understand that the control line was necessary in the invention.
ReplyDeleteControl “means” was indeed necessary. Control line is an example of a control means, hinted by D1 mentioning there can be other means for confirming the test being carried out correctly.
DeleteBesides, without control “means” , it is impossible to know whether the test is valid or invalid. Because the only means to show results is then only a test line. Then the possibilities will be:
Colored test line = positive result (valid)
Uncolored test line = negative result (valid) OR invalid result?
The invention is therefore unclear and unworkable without control “means”.
If I recall correctly, D1 clearly stated that test strips/devices do not always contain a control line. The invention can still function correctly without the control means, therefore it is not essential to the functioning of the 'invention' . I understand what you're saying, in that it may not be clear if the test strip is functioning correctly without the control means but the control means does not actually contribute to the invention (The invention being the conjugate with a specific antibody and gold nanoparticles of diameter 20-100nm). If you claim a control means, then an easy workaround would just be to not include a control means and the infringer would avoid infringement, whilst still having a functioning test strip. But, I wouldn't worry too much, an unnecessary limitation will only be a small marks deduction.
DeleteI also think that including a control line is too limiting, especially in light of D1 stating that "Although the control line is a common feature of most commercially available pregnancy tests, there are some tests available that do not include one and rely on other means to show that the test has been performed successfully".
DeleteThis at least hints on the possibility of using control means separate from the flow test itself, and since our main claim is directed at the product per se, I believe it is important to not exclude a variant which would use a mechanism not included in the test for determining that the test has been performed correctly.
Including a control step in a method claim would have been another case I think, that would be less likely to exclude relevant coverage (but I'm still not sure a control is 100% necessary based on the provided material) but that's not relevant to the product claim.
@Er, agreed. I remember doing some past papers where I included similar limitations, as I thought they were required for the overall device to function. But it became clear that you have to only include features which are essential to the function of the invention, not the device/method as a whole. Otherwise, you limit potential markets for licensing and make yourself easy prey for infringers.
DeleteIt was wrong to claim a lateral test strip? and then the kit comprising the cassette?
ReplyDelete@anonymous, Lateral test strip would still be a 'device' claim so I think you should be okay. I didn't include the cassette as part of the kit, I had it as a dependent claim for the 'device' claim and then the kit comprising the device of any preceding claim and the extraction solution.
DeleteI was a bit unsure regarding the clarity of the term "spherical" so I claimed them as "substantially spherical". I would argue that although the term "substantially" does not appear anywhere in the letter, this is practically the same, at least based on the Guidelines F-IV, 4.7.1
ReplyDeleteI additionally claimed in the independent device claim that the binding of the conjugate due to the second antibodies at the test line leads to the formation of a colored line. Any idea how this may be penalized?
ReplyDeleteRegarding the diagnostic method read G1/04:
ReplyDeleteIt was well-known that an important contribution
to diagnoses performed by physicians in private
practice and in hospitals was the determination
of medical laboratory parameters. Most of these
parameters were concentrations of molecules or
cells in a body liquid (e.g. blood or urine) and
normally determined in vitro. The sample (e.g.
body fluid) was mixed with the reagents in a
reaction vessel, and the detectable change was
evaluated by the instrument which belonged to the
system. Inventions relating to such in vitro
determination of medical laboratory parameters
could in most cases be protected by product
claims. But where method claims were appropriate,
such methods should neither be excluded from
patentability under Article 52(4) EPC, since none
of the method steps was carried out on the body.
Only if direct interaction with the body made a
real difference whether the object of the
invention was achieved, should a diagnostic
method be regarded as falling within the
exclusion under Article 52(4) EPC.
Hi Nils and Nyske, thanks for providing us your solutions.
ReplyDeleteMy main claim has two main differences to yours.
The client stated that the colored particle has to be spherical so that they move with same speed (008).
The client never stated that the gold particle has to be spherical.
The client first tested GoldlöckchenTM colloidal Gold with 40nm particle.(014)
The GoldlöckchenTM colloidal gold contains spherical gold particles and a solvent. D2(002).
They also achieved good results with other types of Gold nanoparticles of other brands. We don’t know what kind of type is meant, but it definitely is not stated that the other gold particle has to been spherical.
On the other hand D2 (002) says that it is well known that a bright red color is achieved with spherical nanoparticles less 100nm and the effect is swinging electron on the surface of the nanoparticle.
Not a chemist, but my understanding is that a suspension containing a nanoparticle an a solvent can still be a nanoparticle.
So my difference to your solution is that I have:
……sperical coloured particle (Ive put in in the state of the art part, cause fig A of D1 is a perspective view, not 2D)
….
characterised in that the coloured particle contains a gold nanoparticle having a diameter of 20 - 100 nm.
In one of my dependent claims the coloured particle also contains a solvent, which forms with the gold particle colloidal gold.
Further a claim with a container +flow test and a flow test set with extraction solution.
I think, in chemistry as far as I understand, colloidal gold does not mean "comprising gold AND solvent in 1 body." It just means that the colloidal/spherical gold is suspended in a solvent, and then we can filter it (maybe by centrifugation or dialysis) out from the solvent to collect the colloidal gold for further use. Solvent is just a means to suspend the colloidal gold, not an ingredient combined within the colloidal gold. I understand that it might not be clear for someone who does not have a background in chemistry.
DeleteThank you Nico and Nyske!
ReplyDeleteDear Nico and Nyske, may I ask you a question? Do you think the feature "the particles have a uniform size" is directly and unambiguously derivable from Fig. A of D1?
ReplyDeleteI believe this feature and the feature that the particles have a spherical shape are essential to ensure that the particles move at a consistent rate. We are not expected to use expert knowledge but this is common general knowledge.
DeleteBut inventive step is a big problem...
DeleteI, again, fed the proposed claim 1 and details of D1 and D2 in ChatGPT, and this was the reply: Not sure how good that is...
ReplyDeleteChatGPT
To assess whether Claim 1 is novel with respect to D1 and D2, and whether it involves an inventive step, we need to analyze the features of the claim in light of the disclosures in the prior art documents D1 and D2.
Novelty Assessment
Claim Features:
A lateral flow test with a sample pad, conjugate pad, and reaction membrane.
The conjugate pad contains a detection agent that is a conjugate of a first type antibody and a colored particle.
The colored particle is specifically defined as a "spherical gold nanoparticle having a diameter of 20 - 100 nm".
D1 Disclosure:
D1 describes a lateral flow test for detecting hCG in urine, using antibodies and latex particles (blue-colored) as detection agents.
It does not mention gold nanoparticles or any specific size ranges for colored particles used in the testing format. Therefore, D1 does not disclose the specific use of spherical gold nanoparticles of the defined size (20 - 100 nm).
D2 Disclosure:
D2 discusses gold nanoparticles, including their properties (spherical shape and size ranging from 5 nm to 400 nm), and mentions their use in various applications including conjugation to biological molecules.
However, D2 does not provide any specific application of these gold nanoparticles in a lateral flow test context, nor does it mention their use in conjunction with antibodies for the detection of specific target molecules like hCG.
Conclusion on Novelty: Claim 1 is novel over D1 and D2 because neither document discloses the specific combination of features in Claim 1, particularly the use of spherical gold nanoparticles with a defined size range in a lateral flow test.
Inventive Step Assessment
To evaluate inventive step, we consider whether the claimed invention would have been obvious to a person skilled in the art, combining the teachings of D1 and D2.
Combination of D1 and D2:
D1 describes a lateral flow test using antibodies and latex particles, but it does not suggest the use of gold nanoparticles. A skilled person in the field might recognize that gold nanoparticles could be used as an alternative to latex particles due to their properties (e.g., color change detection), which D2 highlights.
The specific size range of 20 - 100 nm for gold nanoparticles is not suggested in either document. While D2 provides a range of sizes for gold nanoparticles, the specific application in lateral flow tests and the choice of size range would not be obvious without further experimental validation or motivation.
Technical Advantage:
If using gold nanoparticles in a lateral flow test provides a significant advantage over the existing latex particles (such as improved sensitivity, specificity, or ease of use), this could further support the non-obviousness of the claim.
Conclusion on Inventive Step: Given that the combination of D1 (lateral flow test) and D2 (gold nanoparticles) does not directly suggest the specific implementation of gold nanoparticles in the context of a lateral flow test, and considering that the claim defines particular advantageous properties (spherical shape and specific size), Claim 1 likely involves an inventive step.
Final Assessment
Novelty: Claim 1 is novel with respect to D1 and D2.
Inventive Step: Claim 1 involves an inventive step in view of D1, D2, or a combination of D1 and D2.
Regarding the sentence in par. [015] of the clients letter which says: "We have experimented with gold nanoparticles from other manufacturers and found that any type which has a diameter of 100 nm or less is suitable for our test, since larger particles do not have the necessary red colour."
ReplyDeleteIn the French paper, this sentence is slightly different : "Nous avons réalisé des expériences avec des nanoparticules d'or d'autres fabricants et découvert que tout type ayant un diamètre inférieur ou égal à 100 nm est adapté à notre test, les particules plus larges n'ayant pas nécessairement la couleur rouge nécessaire. " ,
which deepl translates into:
"We have carried out experiments with gold nanoparticles from other manufacturers and found that any type with a diameter of 100 nm or less is suitable for our test, with larger particles not necessarily having the necessary red colour."
To me, the last part of the sentence of the French version i.e. 'larger particles not necessarily having the necessary red colour', imply that particles with a diameter larger than 100nm may have the necessary red colour too and that it is the colour red that is essential here and not necessarily the diameter.
I feel like the teaching of the client's letter to include the restriction on the diameter of the particle is not as clear in the French version than in the English version, which is a pity for those taking the exam in French as I did.
I reviewed the paper. Especially para 14-15 that talk about the diameter of the gold nanoparticles. "found that any type which has a diameter of 100 nm or less is suitable for our test, since larger particles do not have the necessary red colour." I would like to highlight"our test". This needs to read in conjunction with the experiment test done by scientists in para 14. Therefore the diameter of 100m is only a suitability requirement for the experiment tests and not necessarily a limitation on the test device. The only limitations on the diameter on the functionality of the test device is that it must be more than 20nm and the diameter of the gold nanoparticles must be such that the gold nanoparticles oscillate in light with visible colours seen by the naked eye.
ReplyDeleteWithout the 100 nm limitation, the particle may be colourless and you do not have any effect
DeleteThe limitation that the diameter of the gold nanoparticles needs to be such that they oscillate in the light and thereby showing a colour visible to the eye is the limitation I used to overcome issue that particles may be colourless
DeleteIn my opinion, however, your feature is formulated in a task-oriented manner and lacks a concrete solution. You get the solution with the size of the particles, especially with the upper limit.
DeleteHello Niko and Niske. My claim is very similar to yours. I just realised I missed the sentence in par 007 of the client letter. I did not specify in the main claim that the antibody specifically bind the target molecule but I said.... detection agent for detecting a target molecule... and a second antibody for binding the target molecule. Will I lose half of the marks?
ReplyDeleteIn my view, this is more of clarity issue. I hope it doesn’t cost you more than 5-10marks.
DeleteI understood that due to the detection of a very small concentration of the target molecole, some control means are necessary in the new lateral test to be enabling
ReplyDeleteI also included the wicking pad in my main claim. Hope they wouldn't penalize this too heavily (if they indeed view it as non-essential).
ReplyDeleteI considered the OTP over D1 as improved sensitivity allowing detection of low amounts of target molecule. In the invention, the improved sensitivity is given by the gold nanoparticles (in specific size range), but client also tells us that the wicking pad improves sensitivity.
With the information given, there is no certain way to tell if the problem of improved sensitivity is solved in the absence of a wicking pad.
For me, it felt too risky to remove a feature that contributes to solving the problem.
if the wick is inserted in claim 1, and it is deemed not necessary, you will loose marks for an unecessary limitation, but can you still get the marks as if it was in a dependent claim? Otherwise it will be a double penalisation…
ReplyDeleteHence imo you will get -5 to max -8 for that, hope it won't be -15 or something
DeleteDear Deltapatents, I had the whole weekend to see the answer again and analyze the facts. I think you may be wrong for the following reasons to include "100 nm" in claim 1, although 20 nm is an essential feature. The facts are stacked against you.
ReplyDeleteParagraph 0015 of the client's letter states the following:
"We have experimented with gold nanoparticles from other manufacturers and found that any type which has a diameter of 100 nm or less is suitable for our test, since larger particles do not have the necessary red colour."
This does not say anything about the manufacturer GoldiLocks as it clearly is for "other manufacturers". Is the red colour necessary? No. For pregnancy test, red colour is not needed. So if you want the invention to work under the whole scope, 100 nm is certainly not needed.
Let us go to GoldiLocks document D2 to see what it says about 100 nm at paragraph 002:
"Gold nanoparticles absorb and scatter light resulting in colours ranging from vibrant reds
(spherical particles that have a diameter of 100 nm or less) to blues to black and finally
to clear and colourless."
So, it is clear from D2, if you want the lines of colour blues to black as well, which is very well also acceptable for pregnancy tests (see D1), the upper limit of diameter of 100 nm is not needed. Unless you want to indicate that the only colour that matters is the colours "ranging from vibrant reds", there is no need to include 100 nm upper limit.
Thus, non-inclusion of 100 nm should not be penalized by the Examining Committee. This may have an open ground for a quite a bit of appeals (D13/02; reasons 4) on the grounds of ambiguous wording. But I give you the benefit of doubt as you clearly mention "appears to be necessary" in your blog in relation to the feature 100 nm.
I agree with your analysis and hope for the same. The client discloses that particles need to be colored. "[008] The antibodies are attached to small, coloured particles which will provide the visible test result." Whether it is red, blue or black it should not be an essential feature, rather visibility of the color. I think the proposed Delta solution is erring on the side of caution, because it is not clear how the term "necessary" will be interpreted. This is an unnecessary ambiguity introduced in the paper.
DeleteI disagree with the proposed solution on two points:
ReplyDelete1. I doubt that the sample pad (1) is necessary. Honestly, I don't remember writing it or a paragraph that explicitly states that the sample pad (1) has to be there and let’s face it, if the liquid is dropped directly onto the conjugate area, the target molecule (6) will react with the detection agent anyway. It makes no difference.
2. The suggested claim 1 does not reflect that the liquid must reach the reaction membrane (3) in some form. I solved this by incorporating downstream along the capillary flow to show that a liquid is moved.
Am I alone with that assessment?
Dear Sirs,
ReplyDeleteFirst of all, thank you for the proposed correction that helps in seeing what was required to succeed in this exam.
Perhaps, this question below has already be asked and I apologised if it is the case.
The question:
If you had a caracteristic that is not mandatory to the independant claim, you loose points (up to 40 pts over 40 if you've made different ones, considering this independant claim on 40 points).
But will you get 0pts in terms of dependant claims ?
If you get 0pt for dependant claim also, it seems to me to be a double penalisation. But I don't think it is the spirit of the exam (if I look up the compendium). But I have read nothing precisely on it in the compendium...
If this caracteristic was on 2pts for instance, will you get at least 1pt?