Practical Observations concluding John Davies's Patent Cases (1816)
Installment 6 of 6: Miscellaneous Matters, Secrecy and Caveats

Reproduced below is material from Practical Observations concluding John Davies, A Collection of the most Important Cases relating to Patents of Invention (1816). In view of its length and detail, this concluding section of the book is being posted on the blog in six installments.
This sixth installment concerns miscellaneous matters not previously discussed in the Practical Observations. John Davies emphasizes in particular the importance of keeping the invention secret until the patent has “passed the Great Seal”. After the passing of the seal, the patentee was advised to consult others with relevant knowledge and experience who could advise and assist in drawing up the specification. John Davies concludes by discussing caveats and the procedures adopted prior to grant when patent applications interfere with one another.

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It now becomes necessary to state some other matters connected with patents and the rights of patentees, which could not properly be introduced under either of the foregoing heads.
Whenever the patentee brings an action on his patent, if the novelty or effect of the invention be disputed, he must shew in what his invention consists, and that he produced the effect proposed in the manner specified: slight evidence on his part is sufficient, and it is then incumbent on the defendant to falsify the specification. [NOTE: Mr. Justice Buller, in Turner v. Winter, p. 153.]
A patentee, in an action brought by him for infringing his patent, must prove the novelty of every part of that to which his patent applies. [NOTE: Sir Vicary Gibbs, in Manton v. Manton, p. 340, 341.]
In the case Hayne v. Maltby, p. 156, the plaintiffs having a patent machine, covenanted with the defendant that he should use one in the manner described in the specification; in consideration of which he covenanted that he would not use any other. In an action upon the covenant, it was held that the defendant was not estopped by his covenant from pleading in bar to the action, that the invention was not new, or that the patentee was not the inventor, but that he might thus shew that the patent was void, and consequently that he had received no consideration.
But in the case Oldham v. Langmead [NOTE: Cited by Mr. Wigley, in Hayne v. Maltby, p. 157.], where the patentee had conveyed his interest in a patent to the plaintiff, and yet in violation of his contract had afterwards infringed the plaintiff's right; and in his defence attempted to deny his having had any title to convey, stating it not to be a new invention, Lord Kenyon was of opinion that he was by his own oath and deed estopped from making that defence.
An act of parliament having passed for extending the term of a patent for a machine, when in fact the patent was for a process, it was held by Sir James Eyre [NOTE: Boulton v. Bull, p. 218.] that there was nothing technical in the composition or language of an act of parliament, and that it must be expounded not according to the letter but the intent.
An act of parliament enabling a patentee to assign his patent to a greater number of persons than five (to which number it is expressly limited by the patent), and declared to be a public act, does not enable the patentee to make a better title than he could before the act. [NOTE: Hesse v. Stevenson.]
Upon a motion to change the venue in an action for infringement of a patent from Middlesex to Northumberland, it was refused, because the patent, which is the substratum of the action, is tested at Westminster. [NOTE: Cameron v. Gray.]
A patentee having assigned his patent while a suit was depending, reserving the legal estate in the same until the suit should be determined, and covenanting upon the determination of the suit to execute a further assignment, and that until such assignment, the assignee should stand legally possessed of the same; the assignee upon an action brought against him, was nonsuited, upon the ground that no such further assignment had been made; but upon moving for a new trial, it was held by the court that hte legal estate vested without further assignment. [NOTE: Cartwright v. Amatt.]
If the assignees of an uncertified bankrupt, in their own name, executed a deed with other creditors, whereby they release him from all actions, claims, &c. and such deed be not signed by all the creditors, the assignees are not barred from claiming as assignees, the benefit of a patent afterwards obtained. A patent obtained by an uncertified bankrupt is affected by the previous assignment of the commissioners, and vests in the assignees. [NOTE: Hesse v. Stevenson.]
If the assignor of shares in a patent covenants that he has good right to convey, and that he has not, by any means, forfeited any right he ever had over the same; the generality of the former words are not constrained by the latter. [NOTE: Hesse v. Stevenson.]
A person having discovered an improvement upon saddles, communicated his invention to another, who, previously to the communication, undertook by a written agreement not to take any undue advantage of such communication, under the penalty of £1000. He afterwards obtained a patent for this invention in his own name, which the inventor agreed should remain upon certain terms, but which terms the patentee before the action denied, and claimed the improvement as his own invention. In an action to recover the penalty, it was held, that such some could not be considered in the nature of liquidated damages. [NOTE: Smith v. Dickenson, p. 299.]
This case fully shews the necessity of keeping inventions as secret as possible until the patent has actually passed the great seal; for although the defendant was not able to support the patent taken out by him, but agreed at his own expense to assign it to the plaintiff for the remainder of the term, yet the real inventor would have lost the reward of his ingenuity, and the invention would have been laid open to the public at large, had it not been for an expensive and troublesome lawsuit.
It however frequently happens that useful discoveries are made by persons whose circumstances in life will not allow them to bear the expense of obtaining a patent without the assistance of others, who naturally and reasonably expect to be satisfied of the utility and probably success of the invention before they hazard a large sum of money upon a blind speculation; it therefore appears advisable that any agreement between such parties, previously to the disclosure of the invention, should mention a sum, not as a penalty, but with an express declaration that such sum should be considered as liquidated damages, in case of any improper use being made of the discovery, either by bringing it into use before the passing of the patent, or otherwise.
Another instance of the danger an inventor is under of losing the benefit of his invention, by letting it in any way transpire before he has the great seal, may be mentioned, although in this instance it did not succeed. A person had invented an improvement upon spectacles, and as his patent was in a state of forwardness, he had not been sufficiently cautious in keeping the invention to himself, so that another person in the same trade had acquired a knowledge of it, and hastily got a pair made upon the same construction, and exposed them in his window; fortunately, however, the inventor happened to pass the shop, and perceiving them, employed a friend to go an purchase them, in which he succeeded, and his patent passed the great seal the next day, before there was time to get any more made, by which his patent was rendered secure, and most probably a tedious and harassing lawsuit avoided.
As a further confirmation of the necessity of secrecy, we shall only add, that we recollect having heard Lord Eldon, when Chief Justice of the Court of Common Pleas, upon a trial for infringing a patent, say, that during the many years he was first Solicitor-General, and afterwards Attorney-General, so many instances of piracy of inventions had come to his knowledge, that if he was an inventor, he would not disclose his invention to his own brother, until his right was secured by the great seal.
It would therefore be prudent in such cases as machinery, which the inventor, not being perhaps a workman, is unable to construct with his own hands, to employ different workmen to construct detached parts, who are not likely to have any communication with each other, and to be careful not to let them know the connexion or application of the several parts, or the use intended to be made of them.
A person having obtained a patent for an invention, of which he supposed himself the inventor, agreed to let another use it upon payment of a certain annual sum, secured by bond, which sum was paid for several years, when the latter discovering that the former was not the inventor, but that it was in public use before the patent was obtained, brought an action to recover back the amount of the annuity paid, but it was held that he could not recover, as both parties had made the contract in ignorance, and without any fraud. [NOTE: Taylor v. Hare.]
An objection was taken that a specification was not enrolled in due time; but it was held by Lord Ellenborough that the day of the date of the patent is excluded, and therefore if a patent is dated 10th May, and requires the specification to be enrolled within one calendar month next and immediately after the date of the patent, and the specification is enrolled on the 10th June, it is enrolled in due time. [NOTE: Watson v. Pears.]
It now only remains that we should say a few words upon the nature and effect of a caveat, which during our practice we have frequently found to be very much misunderstood. It has been thought by many inventors that upon entering a caveat they secured the right to themselves of obtaining a patent, notwithstanding the invention might be brought into use prior to their having done so; in short, that it was a kind of minor patent, giving them every privilege for one year which the patent itself would do for fourteen, or that it would operate as a proof of their being the first and true inventors, and that upon their afterwards obtaining a patent they would be able to maintain it against any person who, in the mean time, might have made use of the invention; in order to obviate such erroneous ideas, it is necessary to explain the nature and effect of a caveat.
A caveat is merely a desire that if any person should apply for a patent for any particular invention, notice of such application should be given to the party. This caveat is usually entered at the offices of the Attorney and Solicitor-General, and upon an application to either of them for his report upon a petition to the king for a patent for any discovery of the same nature as that described in the caveat, notice is given to the person who has taken this precaution, which gives him an opportunity, if he thinks the inventions interfere with each other, of opposing the application. If it is meant to oppose, the Attorney or Solicitor-General before he makes his report will give a separate audience to each party, and examine the nature of the two inventions, and according to his opinion of their similarity will make his report or not: if he is of opinion that there is a material coincidence, he will not report in favour of the application; but if otherwise, he makes his report, and the patent proceeds in its regular course. If however the party entering the caveat is not satisfied with the decision of the Attorney or Solicitor-General, he has another opportunity of opposing by entering a caveat at the great seal, when the Lord Chancellor will himself give a similar audience and examine the pretensions of the parties. This practice is not often recurred to, as it is attended with much expense, and the Chancellor usually orders all costs to be paid by the party opposing if he does not succeed, as he is averse to the caveat in so late a stage of the business after great part of the expense of the patent has been incurred.
The caveat reamins upon the books for one year, and may be renewed from year to year as long as may be considered requisite.
If it is thought necessary to enter a caveat, it is proper to use general expressions rather than to express the precise invention, as by that means the inventor would receive notice of any application for a patent connected with the subject of the invention mentioned in the caveat, which might not be the case if the particular invention or improvement should be exactly identified. Another reason for general expressions is to guard against the opposite party obtaining a knowledge of the invention, as he might be able to affect the validity of the patent by publishing the invention before the patent is sealed, which would have the effect of throwing the invention open to the public. But it will sometimes happen that two ingenious persons may, without any improper communication, make a discovery of a similar invention, in which case upon the similarity of the invention appearing to the Attorney or Solicitor General, it is usually recommended that the parties should unite interests, and take out a patent in their joint names, which seems to be the most prudent plan for both parties, as priority of invention would be of no avail if the other party should be inclined to publish the invention so as to affect the patent. We cannot however too much reprobate a practice which has of late grown into use by some speculative persons of keeping a list of caveats upon general principles entered in the books without any idea of obtaining patents themselves, but with the sole view of being acquainted with every improvement that is going on, whereby they gain an opportunity of coming to a compromise with the real inventors, and sometimes have obtained large sums of money from them to withdraw their opposition.
With respect to the description or title of the invention, we would observe, that the utmost consideration should be given before the inventor swears to the invention, as the title given in the affidavit and petition cannot afterwards be altered, it is therefore necessary that it should be sufficiently clear to identify the invention, and yet so general as to admit of some degree of latitude in the specification; but the greatest care should be taken that it does not comprehend more than is really the invention of the applicant, as it will be seen by some of the cases reported in this work, that patents have been set aside upon the ground of claiming too much.
But the rock upon which most patents have perished when brought into a court of law is a defective specification, and therefore it is adviseable, particularly in cases of complicated and extensive machinery, or any invention founded upon scientific principles, that the patentee should not depend too much upon his own judgment in drawing up that instrument, but that he should consult men of known and acknowledged science and ability in the particular branch to which the invention relates, who will perhaps not only be assistant towards the elucidation and proper description of the particular invention, but from their general knowledge will be able to point out parts of what the patentee thinks himself to be the inventor which have been previously in use, and which if claimed by him might have the effect of vitiating his patent if ever it should have the misfortune to undergo the ordeal of a court. The patentee may do this without hazard of an infringement upon his patent or any improper use being made of the communication, as the grant having passed the great seal has secured the right to him beyond the danger of imitation.
An additional reason why those skilled in such subjects should be consulted appears to be, that advantage is likely to result from taking the opinion of men who had nothing to do with the invention, as they must necessarily be more likely to give a particular and exact description of an invention than the inventor himself, who from having intimately considered and reflected upon all the parts before it could be brought to maturity, has become so familiar with the whole as to imagine that it was equally clear to others, and that a skilful person might be able to carry the invention into effect by means of such a description as would leave much to be supplied by his own ingenuity and contrivance, which should carefully be avoided.
The foregoing cases and the few imperfect observations here offered to the public will, it is hoped, have the effect of drawing the attention of patentees more particularly to the law of the subject, and enabling them, by knowing what defects have heretofore had the effect of rendering patents void, to make their specifications more clear and explicit than in former times, whereby patents may become more certain, and ingenious persons be induced to promote useful improvements in the arts and manufactures of the country by being acquainted with the means of making the tenure of a patent more stable and solid than of late years it has been found to be; an event much to be desired for the sake of those who devote their time and labour, and are very often at great expense in bringing to perfection things important and advantageous to the trade and commerce of the kingdom.

THE END

Practical Observations concluding John Davies's Patent Cases (1816)
Installment 5 of 6: Enablement and Best Mode

Reproduced below is material from Practical Observations concluding John Davies, A Collection of the most Important Cases relating to Patents of Invention (1816). In view of its length and detail, this concluding section of the book is being posted on the blog in six installments.
This fifth installment concerns the case law requiring inventors to supply specifications that enable those with ordinary skill in the art to construct the invention, and requiring the specification to explain the best mode. It seems that judges in the period 1785—1816 were very strict in applying these enablement and best mode requirements: deficiencies in the specification resulted in the patent being deemed invalid.

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We now come to treat upon a very important part of the subject, and one upon which most of the cases have chiefly turned, and which consequently requires the greatest attention in order to support a patent, namely, what is the description required in the specification.
It was said by Lord Eldon, in Cartwright v. Amatt, that patents are to be considered as bargains between the inventors and the public, to be judged on the principle of good faith, by making a fair disclosure of the invention, and to be construed as other bargains.
It is clearly settled as law, that a man to entitle himself to the benefit of a patent must disclose his secret, and specify his invention in such a way that others may be taught by it to do the thing for which the patent is granted: if the specification be in any part materially false or defective, the patent cannot be supported; but if the specification be such that mechanical men of common understanding can comprehend it, to make the thing by it, it is sufficient; but it must be such that they may be able to make the thing by the specification, without any new inventions or additions of their own. [NOTE: Mr. Justice Buller, in The King v. Arkwright, p. 105.]
A specification is insufficient if a man of ingenuity be required to supply its defects. If sensible men that know something of the business, and mechanics in general, cannot by the specification make the thing invented, it is not so described as to support the patent. [Ibid. p. 128.]
The clearness of the specification must be according to the subject matter of the invention; it is addressed to persons in the profession, having skill in the subject, not to men of ignorance, and if it is understood by those whose business leads them to be conversant in such subjects, it is intelligible. [NOTE: Lord Loughborough, in Arkwright v. Nightingale, p. 56.]
If it appears that a mechanic could not from the specification make an engine with equal effect, or if it required expense and experiments before it could be done, either of those facts would avoid the patent. [NOTE: Mr. Justice Buller, in Boulton v. Bull, p. 194.]
But if the specification be such as to enable artists to adopt the invention, and make the manufacture, it is sufficient; the specification is to be considered as part of the patent. The benefit to the public is from the specification disclosing to the world how others may make and use the same manufacture. To learn what the patent is, you may read the specification and consider it as incorporated with the patent. [NOTE: Mr. Justice Grose, in Hornblower v. Boulton, p. 228, 229, 230.] The patent is nothing without the specification; whether the patent call the manufacture by its name, or style it an invention, a mode, a method, or in any other manner, it signifies nothing, for the specification describing the thing must be resorted to, and my fairly be deemed a part of the patent itself. [NOTE: Ibid. 235.]
It is incumbent on the patentee to give a specification of the invention in the clearest and most unequivocal terms of which the subject is capable; and if it appear that there is any unnecessary ambiguity in the specification, or any thing which tends to mislead the public, the patent is void. [Mr. Justice Ashhurst, in Turner v. Winter, p. 151.] Also if the process as direct by the specification does not produce that which the patent professes to do, the patent is void. The terms of the specification should express the invention in the clearest and most explicit manner, so that a man of science may be able to produce the thing intended, without the necessity of trying experiments. [NOTE: Ibid. p. 152.]
If a thing could only be made with two or three ingredients specified, and the patentee has inserted others which will not answer the purpose, that will avoid the patent. So if he makes the article with cheaper materials than those he has enumerated, although the latter will answer the purpose equally well, the patent is void, because he does not put the public in possession of his invention, or enable them to derive the same benefit which he himself does; slight defects in the specification will be sufficient to vacate the patent. [NOTE: Mr Justice Buller, in Turner v. Winter, p. 154, 155.]
In a case before Lord Mansfied, for infringing a patent for steel trusses, it appeared that the patentee in tempering the steel rubbed it with tallow, which was of some use in the operation, and because this was omitted, the specification was held to be insufficient, and the patent was avoided. [NOTE: Liardet v. Johnson, cited by Mr. Justice Buller in Turner v. Winter, p. 155.]
If a concealment in a specification is not fraudulent but merely inadvertent, if the patentee actually know and meant to practice that mode, and inadvertently did not state the whole in his specification, he must answer for is inadvertence. [Sir Vicary Gibbs, in Bovill v. Moore, p. 414.]
A patent had been granted for a new manufacture of lace, the specification went generally to the invention of mixing silk and cotton thread upon the frame; it was proved that silk and cotton thread had been mixed upon the same frame prior to the patent, although too coarse for lace. The patent not being for any particular mode of mixing, but for making lace of silk and cotton thread mixed, and it having been proved and admitted that silk and cotton thread were before mixed on the same frame in some mode or other, the patent was declared void. [Mr. Justice Buller, in The King v. Else, p. 143.]
Three objections were taken to a specification; first, that after directing lead should be calcined, it directed another ingredient (minium) to be taken, which would not answer the purpose, neither was it said that the minium should be calcined or fused, but if it had reference to the preceding words, then it should be calcined, which would not produce the effect, fusion being necessary. Secondly, that fossil salt was improperly mentioned, there being many kinds of fossil salt, only one of which (sal gem) would answer the purpose, because it must be a marine salt. And thirdly, that all these things put together did not produce the thing intended, and that the patent was for an invention to do three things in one process, whereas one of them could not be produced at all. If either of these objections are well founded, it will avoid the patent. [NOTE: Mr. Justice Buller, in Turner v. Winter, p. 148, 149.]
If a man states in his specification that which is not new, though it was unnecessary for him to do so, he has overstepped his right, and has included that which is not his invention; in that respect his patent is void. [Lord Ellenborough, in Huddart v. Grimshaw,, p. 279.] If he embraces within his invention, as essential parts, any thing which was a part of a prior invention communicated to the public, he has no right to such benefit: no deceptive things are to be held out to the public, those that are material are to be held out as material. [Ibid. p. 294, 295.]
A patentee is bound to confine himself to that which is his invention, and if in the specification he has exceeded the limits of what he has invented, and of which he is intitled to the sole privilege, though in other respects there may be no objection to his patent, that will overturn it, for he will not then have registered a specification of his invention; it will be irregular, in having exceeded the limits of that invention. [Sir Vicary Gibbs, in Bovill v. Moore, p. 390.]
Although an invention be new and beneficial to the public, yet if the plaintiff has in his specification asserted to himself a larger extent of invention than belongs to him; if he states himself to have invented that which was well known before, then the specification will be bad, because that will affect to give him, through the means of the patent, a larger privilege than could legally be granted to him. [Sir Vicary Gibbs, in Bovill v. Moore, p. 404.]
If there existed at the time of taking out a patent engines of which the subject of the patent was only an improvement, then the patent ought to have been only for the improvement; and if the patent could have been supported for an engine, the specification ought to have pointed out those parts only which were the new invention as those to which the privilege applied. [Ibid. p. 411.]
If any material alteration be made from what was before in use, it ought to be specified. If articles are put into a specification merely to puzzle, or which are not useful for the purpose of the patent, the patent is void; for it is not that fair, full, and true discovery which the public have a right to demand. [Mr. Justice Buller, in The King v. Arkwright, p. 118.]
A patent, the object of which was described in the specification to be a perforation in the hammer of a gun-lock for the purpose of letting the air from the barrel pass through, and at the same time secure the powder from passing through, if the perforation permits the powder to pass through with the air, cannot be supported. [NOTE: Lord Chief Baron Thomson, in Manton v. Parker, p. 332.]
It is not necessary to set forth a model or drawing, provided the patentee so describes the invention as to enable artists to adopt it when his monopoly expires. Had a drawing or model been made, and any man copied the improvement and made a machine in a different form, no doubt this would have been an infringement of the patent, because the mechanical improvement would have been introduced into the machine, though the form was varied; the mechanical improvement, and not the form of the machine, is the object of the patent. [NOTE: Mr. Justice Rooke, in Boulton v. Bull, p. 187.]
Articles of a specification which denote intention only, and do not state the thing to which it is to be applied, will not entitle a patentee to maintain an action for a breach of those articles; for he cannot anticipate the protection before he is entitled to it by practical accomplishment. [NOTE: Ibid. p. 187, 188.]
Another consideration respecting the specification, which is also a material one, is whether the patentee has given a full specification of his invention, not only one that will enable a workman to construct a machine answering to the patent, but one that will enable a workman to construct a machine answerable to the patent to the extent most beneficial within the knowledge of the patentee at the time; for a patentee who has invented a machine useful to the public, and can construct it in one way more extensive in its benefit than in another, and states in his specification only that mode which would be least beneficial, reserving to himself the more beneficial mode of practising it, although he will have so far answered the patent as to describe in his specification a machine to which the patent extends, yet he will not have satisfied the law by communicating to the public the most beneficial mode he was then possessed of, for exercising the privilege granted to him. [NOTE: Sir Vicary Gibbs, in Bovill v. Moore, p. 400.]

Practical Observations concluding John Davies's Patent Cases (1816)
Installment 4 of 6: Voiding Patents by Writs of Scire Facias

Reproduced below is material from Practical Observations concluding John Davies, A Collection of the most Important Cases relating to Patents of Invention (1816). In view of its length and detail, this concluding section of the book is being posted on the blog in six installments.
This fourth installment concerns the procedure for voiding patents through writs of scire facias.

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Having shortly stated what is the previous use of a thing which will vitiate a patent, it may be proper to shew for what other causes a patent may be set aside, and by what means.
A writ of scire facias to repeal letters patent lies in three cases: first, when the king doth grant by several letters patent one and the self same thing to several persons, the first patentee may have a scire facias to repeal the second, because it is granted to the prejudice of the first, and the king of right is to permit him, upon petition, to use his name for the repeal of it.
Secondly, when the king doth grant a thing upon a false suggestion, he, by his prerogative, may by scire facias repeal his own grant. A patent may be said to be obtained upon a false suggestion, if it is to the prejudice of the crown or the community, or hurtful to trade by raising the price of the commodity, or in any other way contrary to the terms of the statute of 21 Jac.
And thirdly, when the letters patent express a grant which, by the law of the land, the king cannot make. This may be either against the common law, the statute law, or both, by interfering with the industry of the people, or granting the sole use of any known trade or art, and various other ways which it is not necessary here to enumerate.
A scire facias should be founded upon some record, and therefore to repeal a patent it ought to be in Chancery, where the patent it ought to be in Chancery, where the patent is recorded. The record of the proceedings upon the writ is made up in that court and sent to a court of law to be tried.
But it should be observed that it is not every mistake in a grant which will vitiate a patent, as will be seen by the following general rules laid down by Chief Justice Lee. [NOTE: Buller's Nisi Prius, p. 75.]
1st. Every false recital in a thing not material will not vitiate the grant, if the king's intention is manifest and apparent.
2dly, If the king is not deceived in his grant by the false suggestion of the party, but from his own mistake, upon the surmise and information of the party, it shall not vitiate or avoid the grant.
3dly, Although the king is mistaken in point of law, or matter of fact, if that is not part of the consideration of the grant, it will not avoid it.
4thly, When the king grants ex certa scientia et mero motu, those words occasion the grant to be taken in the most liberal and beneficial sense according to the king's intent and meaning expressed in his grant.
5thly, Although in some cases the general words of a grant may be qualified by the recital, yet if the king's intent is plainly expressed in the body of the grant, the intent shall prevail and take place.

Practical Observations concluding John Davies's Patent Cases (1816)
Installment 3 of 6: “The True and First Inventor”

Reproduced below is material from Practical Observations concluding John Davies, A Collection of the most Important Cases relating to Patents of Invention (1816). In view of its length and detail, this concluding section of the book is being posted on the blog in six installments.
This third installment concerns the case law concerning “the true and first inventor”.

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We come now to consider who have been held to be “the true and first inventors of such manufactures,” and here the plain and ordinary sense of the words seems pretty clearly to explain their meaning; it was however held in the case of Edgeberry and Stephens, p.~36, that any person in this country being in possession of a foreign discovery, and introducing it here, is intitled to a patent, as “if the manufactures be new here, it is within the statute, and whether learned by travel or study, it is the same thing;” and that decision is at this day acted upon to a very great extent, as many patents are granted to persons resident in this country, for inventions communicated to them from abroad, it being only considered necessary under the words of the statute, that they should be new within this realm.
This construction of the act is of great importance, as it is very material to the improvement of the trade and manufactures of this country, that all possible encouragement should be given to the introduction of useful discoveries from every part of the world; and if it had been determined otherwise, it would involve the patentee in very great difficulties, and make it next to impossible for him to support his patent against an infringement, as he would be required to prove the novelty of his invention, if that were disputed, and his opponent might bring evidence from distant parts of the globe to resist the proof.
If an inventor has published his invention before he has taken out his patent, so that the public be in possession of the discovery, he cannot support his patent, although in fact he is the first and true inventor thereof; because the statute requires, not only that they should be “new manufactures within this realm,” but adds, “which others at the time of making such letters, patents, and grants, shall not use.”
It is also required by the statute that such grants be not contrary to law, nor mischievous to the state by raising prices of commodities at home, or hurt of trade or generally inconvenient.
A patent is held to be contrary to law if the patentee is not the sole inventor, as in Tennant's case, tried before Lord Ellenborough, 23d December, 1802. Mr. Tennant brought his action for an infringement of his patent for a bleaching liquor; several witnesses were called in support of the patent, who proved the great utility of the invention, and the general ignorance of the bleachers with respect to such bleaching liquor, until after the date of Mr. Tennant's patent. On the other side, a bleacher near Nottingham deposed, that he had used the same means of preparing his bleaching liquor for five or six years anterior to the date of the patent. He also stated that he had kept his method a secret from all but his two partners, and two servants concerned in preparing it. A chemist in Glasgow deposed, that having had frequent conversations with Mr. Tennant on the means of improving bleaching liquor, he had in one of them suggested to Mr. Tennant that he would probably attain his end by keeping the lime-water constantly agitated. Mr. Tennant afterwards informed the witness that this method had succeeded. These conversations took place in 1796, and Mr. Tennant obtained his patent in 1798. Lord Ellenborough declared this to be a scandalous patent, equally unfounded in law and justice. The plaintiff was nonsuited on two grounds, first, that the process had been used five or six years prior to the date of the patent, and therefore was not a new invention; and secondly, that a chemist had suggested to Mr. Tennant the agitation of the lime-water, which was indispensable in the process, and therefore that it was not the invention of the patentee.
This invention being known before the patent to five different persons, it might perhaps also have been considered as both hurtful to trade and mischievous to the state; hurtful to trade, as confining the use of an article to one person for fourteen years, which was before known to five who might, during that time, have disseminated it to the various persons engaged in that trade, if not prevented by the patent; and injurious to the state, as by granting the exclusive benefit of a thing already used by or known to the public, the patentee could not pay for his privilege in the coin required by the patent, namely, a disclosure of a new invention, having nothing to give as a consideration for his monopoly.
A patent is also contrary to law if the subject of it is not new within this realm; if used by others at the time of granting the patent; if it is mischievous to the state by raising the price of commodities at home; if it is hurtful to trade; or in any other way generally inconvenient, as such patent would be in opposition to the proviso in the statute of 21 Jac.
In the case The King v. Arkwright, p. 79, one of the issues to be tried was, that the patent was prejudicial and inconvenient to his Majesty's subjects in general; but it was held by Mr. Justice Buller that this was merely a consequential issue; it stated no fact which could be tried by a jury, on which the defendant could come prepared to answer, and he therefore refused to hear any evidence on that part of the case.
The next thing proposed is to shew what is that previous use of any thing which will vitiate a patent.
A patent, since the introduction of the proviso for inrolling a specification, is in the nature of a bargain or agreement between the king and the subject, that if the latter will put the public in possession of a beneficial invention found out or introduced into the kingdom by him, he shall have the exclusive benefit of it for fourteen years; but if the public are already in possession of the discovery, the patentee can make no such compensation for the privilege he obtains, and therefore (as mentioned under the last head) if any person has used an article for which a patent is obtained previously to the date of the patent, although he had kept it a secret from all but his two partners and two servants concerned in preparing it; Lord Ellenborough held it such a previous use as to direct a nonsuit upon that ground; but it must have been known to more than one, as in Dollond's case [Cited by Mr. Justice Buller, in Boulton v. Bull, p. 199.] it was held that the discovery having been made before by Dr. Hall, who had confined it to his closet, and the public were not acquainted with it, that was not such a use as would affect the patent; Mr. Dollond was therefore considered as the inventor, and his patent was established.
So in the case of Edgeberry v. Stephens, the thing being practised beyond the sea, however long it may have been so used there, is not such a use as will vitiate a patent granted to the person first introducing it into this country.

Practical Observations concluding John Davies's Patent Cases (1816)
Installment 2 of 6: Unpatentable Subject Matter and “Principles”

Reproduced below is material from Practical Observations concluding John Davies, A Collection of the most Important Cases relating to Patents of Invention (1816). In view of its length and detail, this concluding section of the book is being posted on the blog in six installments.
This second installment concerns what is patentable subject matter. Case law started to develop distinguishing between processes and improvements to processes that resulted in vendible manufactures, considered to be eligible subject, and “principles”, considered to be ineligible subject matter. The cases most often cited by John Davies are Boulton v. Bull and Hornblower v. Boulton.

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Having shewn what is the subject of a patent, it now becomes necessary to cite some authorities shewing what is not the subject of a patent.
A principle cannot be a ground for a patent, because it is the first ground and rule for arts and sciences, or, in other words, the elements and rudiments of them: a patent must be for some new production from those elements, and not for the elements themselves. [NOTE: Mr. Justice Buller, in Boulton v. Bull, p. 196.]
If a principle alone be the foundation of a patent, it cannot possibly stand, though the invention may be a great improvement, yet the patent must be void ab initio. [NOTE: Ibid. p. 197.]
A patent must be for vendible matter, and not for a principle. The organization of a machine may be the subject of a patent, but principles cannot. A patent for the application of a principle, must be as bad as a patent for the principle itself. It seems impossible to specify a principle and its application to all cases; which furnishes an argument that it cannot be the subject of a patent. [NOTE: Mr. Justice Heath, in Boulton v. Bull, p. 192, 193.]
There can be no patent for a mere principle; but for a principle so far embodied and connected with corporeal substances, as to be in a condition to act and to produce effects, there may be a patent. [NOTE: Sir James Eyre, in Boulton v. Bull, p. 212.]
But if a patentee sets forth his invention intelligibly, his specification should be supported, though he professes only to set forth the principle. The term “principle” is equivocal; it may denote either the radical elementary truths of a science, or those consequential axioms which are founded on radical truths, but which are used as fundamental truths by those who do not find it expedient to have recourse to first principles. [NOTE: Mr. Justice Rooke, in Boulton v. Bull, p. 186.]
If a mechanical improvement is intelligibly specified, whether the patentee calls it a principle, invention, or method, or by whatever other appellation, the court are not bound to consider his terms, but the real nature of his improvement, and the description he has given of it, and may protect him without violating any rule of law. [Ibid. p. 187.]
A patent cannot be granted for a mere principle; yet if the thing is to be made or done by a manufacture, and the mode of making that manufacture is described, it then becomes an effect, but whatever name it may be called, not a patent for a mere principle, but for a manufacture, for the thing so made, and not for the principle upon which it is made. [Mr. Justice Grose, in Hornblower v. Boulton, p. 234, 235.]
It appears, therefore, from these authorities, that there cannot be a patent for a mere philosophical principle, neither organized nor capable of being so; but that a patent for a machine improved by a philosophical principle, though the machine existed before, is good.
The grant of a method is not good because uncertain; the specification of a method or of the application of a principle is equally so. [Mr. Justice Heath, in Boulton v. Bull, p. 198.]
The method or mode of doing a thing are the same, a patent cannot be supported for a method only, without having carried it into effect, and produced some new substance. Unless a patent can be supported for a manufacture, it cannot be supported at all. [NOTE: Mr. Justice Buller, in Boulton v. Bull, p. 198.] A method of doing a thing, without the thing being done, or actually reduced into practice, is not a good foundation for a patent; when the thing is done or produced, then it becomes the manufacture, and is the proper subject for a patent. [NOTE: Ibid. p. 199.]
In words the privilege granted is to exercise a method of making or doing any thing, yet if that thing is to be made or done by a manufacture, and the mode of making that manufacture is described in the specification, it then becomes an effect, but whatever name it may be called [NOTE: Mr. Justice Grose, in Hornblower v. Boulton, p. 235.]
Patents for a method or art of doing particular things have been so numerous, that method may be considered as a common expression in instruments of this kind; it would therefore be extremely injurious to the interests of patentees, to allow this verbal objection to prevail. [NOTE: Mr. Justice Rooke, in Boulton v. Bull, p. 185.]
Mr. Hartley,s invention for securing buildings from fire is no substance or composition of things, it is a mere negative quality, the absence of fire: the effect is produced by a new method of disposing iron plates in buildings, the patent therefore could not be for the effect produced, nor for making the plates of iron, which, when disposed in a particular manner, produce the effect, for those are things in common use; but for the method of disposing those plates of iron so as to produce the effect, and that effect being a useful and meritorious one, the patent was very properly granted to him for his method of securing buildings from fire. Plates of iron are the means employed, but he did not invent those means; the invention wholly consisted in the new method of using, or rather disposing of a thing in common use, which every man may make. [NOTE: Sir James Eyre, in Boulton v. Bull, p. 208, 209.]
It appears therefore that if a patentee denominate his discovery “a method,” when in fact the thing invented is something substantial, or a new and useful effect, produced by a new application of means before in use, the verbal inaccuracy will not vitiate the grant.
If a man by science devise the means of making a double use of a thing known before, he could not have a patent for it. [NOTE: Mr. Justice Buller, in Boulton v. Bull, p. 197.]

Practical Observations concluding John Davies's Patent Cases (1816)
Installment 1 of 6: Patentable Subject Matter

Reproduced below is material from Practical Observations concluding John Davies, A Collection of the most Important Cases relating to Patents of Invention (1816). In view of its length and detail, this concluding section of the book is being posted on the blog in six installments.
This first installment concerns what is patentable subject matter.

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John Davies, A Collection of the most Important Cases relating to Patents of Invention (1816)

Practical Observations

PRACTICAL OBSERVATIONS
RESULTING FROM
THE FOREGOING CASES.

From these cases we may be led briefly to consider what is and what is not the subject of a patent, and who is the first inventor; what is that previous use of any thing which will vitiate a patent; what is the description required in the specification; and lastly, to state some matters connected with patents not coming under either of those heads; and in pursuing those points, that proper authorities may be given for what is hereafter laid down, we shall as much as possible avoid using any language of our own, but shall chiefly make use of the language of the learned judges, referring to the cases in which they have made the observations hereafter stated.
First, as to what is the subject of the patent. The sixth section of the statute of 21 Jac. for restraining monopolies, provides that any declaration contained in the said act “shall not extend to any letters patent and grants of privilege for the term of fourteen years or under thereafter, to be made of the sole working or making of any manner of new manufactures within this realm, to the true and first inventor or inventors of such manufactures, which others at the time of making such letters patent and grants shall not use, so as also they be not contrary to the law, nor mischievous to the state, by raising prices of commodities at home, or hurt of trade, or generally inconvenient.”
The chief design of this act evidently was to restrain the prerogative of the crown in respect to monopolies which had before been carried to a very mischievous extent, but reserving a power for the salutary exercise of such prerogative in the case of new and beneficial inventions.
Prior to this statute, the courts had been very much embarrassed with a great variety of cases upon royal grants of monopolies, which had been mostly determined to be invalid, either as being against the common or statute law, or both; but this act, declaratory of the law upon the subject, has since rendered the matter more certain.
We will begin with the words of the proviso, and shew in the first place what have been held to be “new manufactures.” The word manufacture is of extensive signification: it applies not only to things made, but to the practice of making, to principles carried into practice in a new manner, to new results of principles carried into practice. Under things made, we may class new compositions of things, such as manufactures in the most ordinary sense of the word: all mechanical inventions, whether made to produce old or new effects, for a new piece of mechanism is certainly a thing made. Under the practice of making, we may class all new artificial manners of operating with the had, or with instruments in common use, new processes in any art producing effects useful to the public. [NOTE: Sir James Eyre, in Boulton v Bull, p. 207.] New methods of manufacturing articles in common use, where the whole merit and effect produced are the saving of time and expense, and thereby lowering the price of the article, may be said to be new manufactures, in one of the common acceptations of the word, and agreeable to the spirit and meaning of the act. [Ibid. p.210.]
If a patentee claims a monopoly for an engine or machine, composed of material parts, which are to produce the effect described, and the mode of producing this is so described as to enable mechanics to produce it, it is a patent for a manufacture, which is something made by the hands of man, and the patent is good. No technical words being necessary to explain the subject of a patent. [NOTE: Lord Kenyon, in Hornblower v Boulton, p. 225.]
A new combination of old materials so as to produce a new effect, is the subject of a patent. [NOTE: Lord Ellenborough, in Huddart v. Grimshaw, p. 267.] In inventions, through the medium of mechanism, there are some materials which are common, and cannot be supposed to be appropriated in the terms of any patent. There are common elementary materials to work with in machinery, but it is the adoption of those materials to the execution of any particular purpose that constitutes the invention; and if the application of them be new; if the combination in its nature be essentially new; if it be productive of a new end, and beneficial to the public, it is that species of invention, which, protected by the king's patent, ought to continue to the person the sole right of vending it. [NOTE: Lord Ellenborough, in Huddart v. Grimshaw, p. 278] If he states any particular thing before in common use, applied in a new manner to the production of, and effecting a new end, that is part of the substance of the invention. [NOTE: Ibid. p. 279.]
It is no objection to mechanical or chemical discoveries, that the articles of which they are composed were known and in use before, provided the compound article is new; but the patent must be for the compound article, and not for all the articles or ingredients of which it is made. [NOTE: Mr. Justice Buller, in Boulton v. Bull, p. 199.] A man took out a patent for water tabbies; suppose painted floor-cloths to be produced on the same principle, they are distinct substances, calculated for different purposes, and were each unknown to the world before; therefore, a patent for one would be no objection to a patent for the other. [NOTE: Ibid. p. 200]
In the case Morris v. Branson [NOTE: Cited by Mr. Justice Buller, in Boulton v. Bull, p. 202.], an objection wsa taken that it was not a new invention, but only an addition to an old machine. Lord Mansfield said, that objection would go to repeal almost every patent that ever was granted. The verdict in that case was for the plaintiff, and was acquiesced in; and although his lordship said he had paid great attention to the point, and mentioned it to all the judges, he did not state what was their opinion, or give any direct opinion himself, yet it may be safely collected, that he thought the patent good, and since that time it has been the generally received opinion that a patent for an addition is good, but it must be for the addition only, and not for the old machine too. If a patent be confined to the invention of a particular part, it gives no right to the whole engine, or to any thing beyond the invention itself; the public have the right to purchase that improvement by itself, without being incumbered with other things. [NOTE: Mr. Justice Buller, in Boulton v. Bull, p. 203.]
In Jessop's case [NOTE: Cited by Mr. Justice Buller, in Boulton v. Bull p. 203.] his patent was avoided because it was taken for the whole watch, when the invention consisted of only one movement. A person has a right to purchase the new movement and work it up in watches made by themselves.
When the effect produced is some new substance or composition of things, the patent ought to be for such new substance or composition, without regard to the mechanism or process by which it has been produced. When the effect produced is no substance or composition of things, the patent can only be for the mechanism or for the process. [NOTE: Sir James Eyre, in Boulton v. Bull, p. 208.]
If the machinery be not new, but only conducted by the skill of the inventor, so as to produce a new effect, the patent cannot be for the machinery. [NOTE: Sir James Eyre, in Boulton v. Bull, p. 210.]
If the prosecution of a manufacture be assisted (as in a lace machine) by bending together two of the teeth of the dividers, or making one longer than the rest, if it appears to have been a subsequent discovery it will not break in upon the validity of a patent, it will only shew that the patentee has since found out the means of carrying on his own invention to better effect [NOTE: Sir Vicary Gibbs, in Bovill v. Moore, p.~381.]; but if at the time when he obtained his patent he was apprized of this more beneficial mode of working, and did not by his specification communicate this more beneficial mode of working to the public, that will have been a fraudulent concealment from the public, and will render the patent void. [NOTE: Ibid. p. 401.]
A patent can only be for the additional improvement described in the specification, and the patentee cannot claim the sole manufacture of the whole engine [NOTE: Mr. Justice Grose, in Hornblower v. Boulton, p. 233.] It signifies nothing whether the patent be for the engine or for the method of making it, if that method be sufficiently described in the specification. [NOTE: Ibid. p. 236.]
In Williams v. Brodie [NOTE: Cited by Mr. Bearcroft, in the King v. Arkwright, p. 97.] it was held that if a new invention which is the ground of a patent is the addition of a new application to an old machine, it should be so described in the patent; but in the case of Harmar v. Playne [NOTE: Page 324.], a patent for improvements upon a former machine was held good, although the specification described the whole machine without distinguishing the improvements from the parts of the old machine, or referring to the former specification otherwise than as the second patent recited the first.
A patent for an improvement upon a thing, or for the thing improved, is in substance the same. [NOTE: Mr. Justice Heath, in Boulton v. Bull, p. 191.]
In the case of an invention, many parts of a machine may have been known before; yet if there be any thing material and new, which is an improvement, that will be sufficient to support a patent; but whether it must be for the new addition only, or for the whole machine, is another question. [NOTE: Mr. Justice Buller, in The King v. Arkwright, p. 218, 129.] If in a carding machine, the carding cylinder was before used covered all over, and a patent be taken for a cylinder covered in stripes, and it operates as well and answers the same purpose without stripes, suppose stripes never to have been used before, that is not such an invention as will support a patent. [NOTE: Ibid. p. 137.]
If the novelty of an invention consists in the new conformation of its parts, and the new conformation of all those parts is of the patentee's invention, then, although every one of the parts was old, he would be intitled to a patent for a machine composed by that new conformation of the whole; but if another person had combined all those parts up to a given point, and the patentee took up his combination at that point, and went on combining beyond that, if the subsequent combinations alone were his invention, the former combinations he will have no right to. [NOTE: Sir Vicary Gibbs, in Bovill v. Moore, p. 412.]
If he has only invented an improvement of the old engine, or of any one or two engines which existed before, then his specification by which he claims the whole to himself will be bad. If on the other hand he has invented an engine which consists of a perfectly new conformation of parts, although all the parts were used before, yet he will be intitled to support his patent for a new machine. [NOTE: Ibid. 412, 413.]
In order to support a right to the exclusive enjoyment of any invention, it is necessary that the party who takes out the patent should shew that the invention is new, that it is not only new but useful, and that he has accurately explained the nature of his invention in his specification, separating that which is new from that which is old, so as to enable a person of tolerable skill to make the thing by his specification. [NOTE: Sir Vicary Gibbs, in Manton v. Manton, p. 348, 349.]
It is no matter that two patents profess the same object. If springs are not an essential part of the invention, and they are specified as an essential part, it would certainly affect the patent. If the spring should be a material part of the invention, and relied upon as such in two patents, and if it is the same, the latter patentee cannot take the benefit of it. [NOTE: Lord Ellenborough, in Huddart v. Grimshaw, p. 294, 295, 296.] If a patent be taken for that to be done by a tube which was before done by a ring or circle, the patent would be good, for that is a substantive invention. [NOTE: Ibid. 297, 298.]
In point of law it is necessary that a plaintiff should prove his invention to be new and useful, in order to intitle himself to an action. [Sir Vicary Gibbs, in Bovill v. Moore, p. 399.]
A patent taken out for “a method of more completely lighting cities, towns, and villages,” when the specification described improvements upon street lamps, was held to be taken out too large; it was in substance a patent for an improvement in street lamps, and should have been so taken. [Mr. Justice Le Blanc, in Lord Cochrane v. Smethurst, p. 361.]
The subject of a patent ought to be specified, and ought to be that which is vendible, otherwise it cannot be a manufacture. [NOTE: Mr. Justice Heath, in Boulton v. Bull, p. 191.]
Next as to “new manufactures within this realm.” It has been held that if an invention be new in England, a patent may be granted for it, though the thing was practised beyond the sea before. [NOTE: Edgeberry v. Stephens, p. 36.]