injurious to the value of a patent, it is very desirable that all such citations should be carefully considered and argued or amended away. The charge for this step varies from one pound upwards according to the complexity of the case.

An appeal can be made from the decision of the Comptroller under this section to the Law Officer.

It is no part of the examiner's duty to examine into the validity of the specification or the novelty of the invention, otherwise than as regards these fifty years of British complete patent specifications; and though the claims may be clearly bad, it is his duty to pass them unaltered, if in form and based on the provisional specification, and not covered by these prior patent specifications.

ADVERTISING.

When the complete specification (whether filed instead of a provisional, or in pursuance of a provisional previously filed) is accepted by the Comptroller, it is immediately advertised as open to public inspection, and any one can examine it at the Patent Office, or obtain a copy of it on paying the cost of transcribing.

It is also put in the hands of the King's printers and printed in due course, usually about three weeks after acceptance. It can then be purchased for one shilling a copy, including postage and agency.

OPPOSITION.

During the ensuing two months after acceptance of the complete specification, any person is at liberty to oppose the grant of the patent, on the ground that the applicant has obtained the invention from him, or from some one of whom he is the legal representative, or that it has been the subject of a prior patent

or patents in one of which the opponent has, or had before it became public property, a beneficiary interest, or that it includes an invention not set forth in the provisional specification for which the opponent has since the filing of the provisional specification applied for a patent. If an opposition be entered, the matter is adjudicated upon by the Comptroller of Patents, but the parties have the right of appeal to the Attorney or Solicitor-General.

If the points in dispute involve technicalities beyond the knowledge of the Law Officer, he is allowed to call in a man eminent in the line of business to which the invention relates to assist him as assessor. The Law Officer has the power of making either party pay a part or all of the other's costs as he may think just, but seldom allows more than five to seven guineas.

In these oppositions it is not necessary to employ a barrister, and, indeed, with a few exceptions (counsel making a speciality of patent work), a good patent agent makes at these hearings a better advocate than a barrister.

No costs are allowed for the hearing before the Comptroller.

In these cases the person who first makes an application for the patent is held, in default of conclusive evidence to the contrary, to be the first inventor, and, though the patent may be granted to each separately if no opposition be made to the second, yet the owner of the patent of earlier date has the sole right and title to the new matter common to both patents (if claimed by him), and the second cannot use it without the first's permission.

Two or more inventors effecting the same result but by different means, can each obtain a valid patent for his mode of procedure, provided said modes are substantially different.

A patent granted to the true and first inventor is not invalidated by a prior application made in fraud of him, nor by any sale, publication, or working of the invention made subsequent to the fraudulent application, and during the period of provisional protection; and where a patent has been revoked or cancelled by order of the Court on the ground of fraud, the Comptroller of Patents may, on the application of the true inventor made in due form, grant him a patent in lieu of and bearing the date of the revocation of the fraudulent patent; but the new patent will be only issued for the remainder of the term for which the revoked patent was granted, and it is somewhat doubtful whether such patent will be valid, as the invention will have been published before its date. We think, however, the courts will hold that the new patent will hold good against any publication which has taken place since the date of the revoked patent.

This clause is construed not to apply to inventors resident abroad taking out patents as communications. In a case where A. in New York had invented a machine in 1886, and in 1887 B. entered his employ, saw the machine, and forwarded the particulars to C., a British Patent Agent, who took it out as a communication from B., the day before D., another Patent Agent, applied for it as a communication from A., it was decided that as A. and D. could not prove that C. (the agent) had obtained the invention dishonestly, the latter was the "true inventor" and the fraud committed by B., the communicator abroad, was immaterial to the case.

Also in a case where B., a person abroad, was shown to have stolen the invention from a subsequent applicant, also resident abroad, the officials allowed the patent to the first applicant on the ground that they cannot take cognisance of a fraud committed outside the realm.

SEALING.

If no opposition be entered, or the case be decided in favour of the applicant, the patent is passed for sealing with the Seal of the Patent Office, and if sealed is dated as of the day of the original application, except in the case mentioned under the heads, "First and Second Examination."

It will not be sealed, however, except on formal application and payment of the Sealing fees. The cost of this step is £1 10s.

Where the sealing is delayed by an appeal to the Law Officer, or by opposition to the grant of the patent, the patent may be sealed at such time as the Law Officer may direct, otherwise it must be sealed within twelve months (or fifteen months where the time for accepting the final specification has been officially extended) of the date of application, or it is void.

Saving and except that if the person making the application dies before the expiration of fifteen months from the date of application, the patent may be granted to his legal representatives, and sealed at any time within twelve months after the death of the applicant.

COST OF BRITISH PATENTS.

This varies necessarily with the complexity of the invention.

Provisional protection for nine months is usually £3 3s. to £4 4s.; complete specification, exclusive of cost of drawings, £8 8s. to 12 12.; or complete protection at start 10 10s. to £14 14s. Drawings, draughtsman's time, at from 15. to 2s. 6d. an hour, according as it is copying or designing. Argument and amendment before the examiner £1 upwards; appealing from the decision of an examiner

including personal hearing before the Comptroller £3 upwards.

Sealing patent, £1 10s.

These charges include everything except fighting oppositions and appeals, which only occurred before the examination system was introduced about one time in sixty.

The cost of oppositions varies very greatly, some going as low as three or four pounds, others amounting to a hundred or two; average cost about £23, and rarely going above £50.

Cost of appeals to the Law Officer are from £10 10s., and £3 35. to (in rare cases) £10 105. are usually awarded to the winning party as costs, to be paid by the loser.

SUBSEQUENT TAXES.

A patent once sealed and issued is free from all further payment or formalities until the end of the fourth year, at and after which period the following stamp duties or taxes are payable, or the patent becomes void :

The agency fee for attending to the payment of these

taxes is usually 10s. 6d.

One or more of all these duties can be paid at once