Statement of problem: What are the procedures for patent opposition laid down by countries like USA and Europe and their significance on comparison to Indian patent laws?
Many countries have laid down a procedure, in patent laws whereby a person can express his opposition against the grant of a patent or against a granted patent, by filing an opposition with the patent office of the respective country. There are two types of opposition for grant of patents: pre-grant opposition and post grant opposition. An opposition filed before the grant of a patent is called a pre grant opposition and an opposition filed after the grant of a patent is called a post grant opposition. Some countries allow both types of oppositions while some countries allow only one of the two types, based on their respective patent laws.  Further, there are various grounds specified by the patent laws of different countries on the basis of which an opposition can be filed. Some of the common grounds are non-compliance with the patentability criteria and insufficient disclosure of the invention in the specifications. Sometimes a significant prior art which was not discovered during the examination stage of a patent application, but was known by a third party may also form the basis of an opposition. The advantage of having a pre-grant opposition system is that it precludes bad or frivolous patents from getting granted. However, a common drawback of a pre grant opposition system is that it may cause a delay in grant of a patent. Similarly, the major short coming of a post-grant opposition system is that it leads to a wrongful monopoly of a patent holder until the time an opposition is filed for the patent.  This project discusses about the opposition procedures as provided in India, Europe and USA based on their respective patent laws.
OPPOSITION PROCEDURE IN INDIA
In India, the Patents Act 1970 (hereafter referred as The Act) lay down provisions regarding filing opposition for a patent. However, the original act only provided a post-grant opposition system. The Indian patent system was revolutionized on 1st January, 2005 when India signed the Trade Related Aspects Intellectual Property Rights (TRIPS) agreement. Section 25 of The Act was amended  in light of the TRIPS agreement to introduce a ‘mixed’ system of both pre-grant and post-grant opposition in India.
PRE-GRANT OPPOSITION IN INDIA
Any person can represent for opposition, in writing, to the Controller General of Patents, Designs and Trade Marks of India (henceforth referred to as Controller), against the grant of a patent after the application for a patent has been published but a patent has not been granted. The pre-grant opposition procedure acts as a safety net to capture questionable patent applications before a patent is granted on them.  The pre-grant opposition can be filed on a number of grounds as specified under section 25(1) of The Act as following:
Wrongfully obtaining the invention Prior publication in India or elsewhere
Prior claiming in India
Prior public knowledge or public use in India
Obviousness and lack of inventive step
Not an invention under The Act or the invention not patentable under The Act
Insufficient description of the invention
Failure to disclose information or furnishing false information pertaining to related foreign filing
Patent application not filed within 12 months of filing the first application in a convention country
Wrongful mention of source and geographical origin of biological material used for the invention
Invention anticipated with regard to traditional knowledge of any community, anywhere in the world 
PROCEEDINGS UNDER PRE-GRANT OPPOSITION
Any person can file a pre-grant opposition to the Controller against the grant of patent on any of the grounds mentioned above. The representation is required to include a statement, a request for hearing and evidence (if any) in support of the representation. A representation is required to be filed within a period of 6 months from the date of publication of the patent application. The controller considers the representation only after a request for examination for that patent application has been filed. After considering the representation, the controller notifies the applicant with a copy of the representation. The applicant is required to reply to the notification with his statement and evidence (if any) in support of his application within three months from the date of the notice. The Controller then based on the statement and evidence filed by the applicant either refuses the grant of the patent or asks the applicant for amendment of the complete specification to his satisfaction. Finally, after considering the representation and response by the applicant the controller proceeds further by either rejecting the representation and granting the patent with amendments to the complete specification or accepting the representation and refusing the grant of the patent within one month from the completion of above proceedings. 
POST-GRANT OPPOSITION IN INDIA
According to the Act, a notice for a post-grant opposition can be filed by any interested person before the expiry of a period of one year from the date of publication of grant of the patent. According to The Act, an interested person  includes a person engaged in, or promoting research in the same field of invention. Similar to the pre-grant opposition, a post-grant opposition can be filed on a number of grounds as specified under section 25(2) of The Act as listed below.
PROCEEDINGS UNDER POST-GRANT OPPOSITION
Any interested person can oppose a granted patent by giving a notice of opposition to the Controller on any of the grounds mentioned above within one year from the grant of the patent.
An opponent is required to submit a written statement to the Controller, setting out the nature of his interest, the facts upon which he bases his case, relief which he seeks and evidence, if any, along with the notice of opposition. The opponent is also required to send a copy of the statement and evidence if any to the patentee. On receipt of the notice of opposition, the Controller notifies the patentee regarding the notice of opposition.
The Controller then constitutes an opposition board consisting of three members and nominates one of the members as the Chairman of the Board. Also, the examiner who dealt with the application for patent during the proceeding for grant of patent is not considered eligible to be a member of the opposition board.
If the patentee desires to contest the opposition, the patentee is required to send a reply statement at the appropriate patent office setting out the grounds on which the opposition is contested and evidence if any, in support of his case within a period of two months from the date of receipt of the copy of the written statement and opponent’s evidence. The patentee is also required to send a copy of the reply statement to the opponent.
However, if patentee does not desire to contest the opposition or fails to send his reply and evidence within the specified period, the patent is considered to have been revoked.
The opponent may file evidence in reply at the appropriate office, within one month from the date of delivery to him of the copy of the patentee’s reply statement and evidence. The opponent is also required to send a copy of his reply evidence to the patentee.
No further evidence can be delivered by either party except with the direction of Controller provided such directions are prayed before the Controller has fixed the hearing.
The opposition board then examines the notice of opposition and the filed document mentioned above, and submits a report with reasons on each ground mentioned in the notice of opposition, with its joint recommendation within 3 months from the date on which the documents were forwarded to the board.
Further, the Controller fixes a day and time for a hearing after completion of presentation of evidence if any, and on receiving the recommendation of Opposition Board. The Controller gives the parties at least 10 days notice for the hearing. Any party desiring to be heard is required to inform the Controller through a notice along with payment of prescribed fees. If neither party is desirous of being heard, then no hearing takes place and the Controller only considers the recommendation of the Board.
After hearing and considering recommendations of the Opposition Board, the Controller decides the opposition case and notifies the parties of his decision and costs awarded if any, giving reasons there for.
LANDMARK CASES OF OPPOSITION IN INDIA
Novartis AG vs. Natco Pharma Ltd. 
An application for patent was filed in India on 17th July, 1998 by Novartis AG, Switzerland, claiming Switzerland priority date of 18th July, 1997. Upon publication, the grant of patent was opposed by Natco Pharma Ltd., India on 26th May, 2005. The grounds for opposition were:
Anticipation by prior publication
Lack of inventive step
Non-patentability under section 3(d)
Wrongfully claiming the priority
The title compound was already known in a US patent (filed in 1993). The US patent claimed a pharmaceutically acceptable salt of the base compound. Another Document, “Nature Medicine” (5th May, 1996) also described the title compound. Also, the claimed salt inherently existed in the most stable form of the salt. Hence, the claims of the application for the product and process in respect of the title compound stood anticipated by prior publications. Additionally, based on section 3(d) the product claim amounted to a mere discovery of the new form of the known substance. Further, the application had claimed Swiss priority, but Switzerland was not a convention country on the date of filing in Switzerland. Hence, no priority of Swiss application could be claimed in respect of the Indian application.
In view of the above findings and arguments the Controller ruled that the above patent application cannot proceed for grant of patent.
Hindustan Lever Ltd. vs. Godrej Soaps 
In another landmark case a patent filed by Hindustan Lever Ltd. on 14th Oct., 1992 in India was opposed by Godrej Soaps Ltd. The patent had two priorities of UK dated 14th Oct, 1991 and 14th July, 1992 and was granted on 18th May, 1996 in India. The grounds of opposition were:
Prior public use and prior public knowledge
Obviousness and lack of inventive step
Insufficiency and clarity of description
The applicant has failed to disclose to the Controller the information required by section 8 or has furnished the information which in any material particular was false to his knowledge.
After the hearing it was concluded that the teachings of the cited exhibits were insufficient to prove the grounds of opposition mentioned above. The applicant amended the claims and specifications to make their point clear and to overcome the opponent’s allegations.
After considering notice of opposition, statements and evidences from both of the parties and hearing, the opposition was dismissed.
OPPOSITION SYSTEM IN EUROPE
European Patent Office (EPO) has a system of post-grant opposition.  According to Article 99  of the European Patent Convention (EPC), an opposition for a European patent (henceforth referred to as EP patent) can be filed by any person within nine months of the publication of the mention of the grant of the EP patent in the European Patent Bulletin (EPB). An opponent is required to give a notice to the EPO of opposition to that EP patent along with payment of required fees. The opposition applies to the EP patent in all contracting states in which that EP patent has effect. Opposition may only be filed on the following grounds under Article 100 of EPC:
Subject matter of the EP patent is not patentable
The EP patent does not disclose the invention in a manner sufficiently clear and complete for it to be carried out by a person skilled in the art
Subject matter of the EP patent extends beyond the content of the application as filed, or, if the patent was granted on a divisional application or on a new application filed beyond the content of the earlier application as filed.
PROCEEDINGS UNDER OPPOSITION AT EPO
Any person may give notice of opposition to an EP patent with prescribed fee to the EPO, within nine months of the publication of the mention of the grant of the EP patent in the EPB.
Notice of opposition is required to be filed in a written reasoned statement. The notice of opposition should contain particulars of the opponent, number and title of the EP patent against which opposition is filed, name of the proprietor of the patent (also known as patentee), a statement of the grounds on which the opposition is based, as well as an indication of the facts and evidence presented in support of these grounds.
An Opposition Division is formed by the EPO for the examination of opposition against the EP patent. An Opposition Division consists of three technically qualified examiners; at least two of them are those who were not a part of the proceedings for grant of the EP patent facing opposition.
If the notice of opposition does not comply with the desired requirements, the Opposition Division rejects the opposition as inadmissible, unless the deficiencies are remedied within a specified time period.
The Opposition Division communicates the notice of opposition to the proprietor of the EP patent and gives him the opportunity to file his observations and to amend, where appropriate, the description, claims and drawings within a specified period of time.
If several notices of opposition have been filed, the Opposition Division communicates them to the other opponents.
The Opposition Division also communicates any observations and amendments filed by the proprietor of the EP patent to the other parties and may invite the other parties to reply within a specified time period.
The Opposition Division examines those grounds for opposition which are invoked in the opponent’s statement. Grounds for opposition not invoked by the opponent may also be examined by the Opposition Division of its own motion if they would prejudice the maintenance of the European patent. During the examination, the Opposition Division invites the parties, as often as necessary, to file observations on communications from another party or issued by itself.
If the Opposition Division is of the opinion that at least one ground for opposition prejudices the maintenance of the EP patent, the Opposition Division revokes the EP patent, else, the Opposition Division rejects the opposition.
If however, the Opposition Division after considering the amendments made by the proprietor of the EP patent during the opposition proceedings is of the opinion that the EP patent meets the requirement of the EPC, it maintains the EP patent as amended; else, it revokes the EP patent.
If the EP patent is maintained as amended by the Opposition Division, the EPO publishes a new specification of the EP patent as soon as possible after the mention of the opposition decision has been published in the EPB.
RE-EXAMINATION PROCEDURE IN USA
USA has the provision of a re-examination procedure to challenge the validity of a granted patent.  Any person (or a third-party) at any time during the period of enforceability of a patent, may cite to the United States Patents and Trademarks Office (USPTO), any prior art which that person believes to have a bearing on the patentability of any claim of a particular patent. A request for re-examination by the USPTO is required to be filed in writing along with the payment of required reexamination fee by the requestor. The request is also required to set forth the pertinency and manner of applying cited prior art to every claim for which reexamination is requested. 
There are two types of re-examination procedures in USA: Ex parte re-examination and inter partes re-examination. Congress introduced ex parte reexamination in 1980 to provide a vehicle for a third party or patent owner to obtain reexamination of a patent. Ex parte re-examination of patents, and the procedures for same, were established by Congress to serve as an expedited, low-cost alternative to patent litigation for reviewing only certain aspects of patent validity, based on patents and printed publications. However, subsequent Congressional review indicated infrequent use of ex parte re-examination, primarily because a third party who requested re-examination was unable to participate in the examination stage of the re-examination after initiating the reexamination proceeding. To address these concerns, Congress enacted the “Optional Inter Partes Reexamination Procedure Act of 1999” as Subtitle F of the “American Inventors Protection Act of 1999” (AIPA). Under the inter partes re-examination procedure, the third party can participate in the examination stage of the reexamination proceeding, appeal to the USPTO’s administrative Board of Patent Appeals and Interferences (BPAI) and participate in the patent owner’s appeal to the BPAI.
A re-examination proceeding is concluded by publication of a re-examination certificate. The certificate amends the text of the patent that was re-examined, in a manner similar to a certificate of correction. The re-examination certificate contains the text of all changes to the text of the patent that was the subject matter of the re-examination proceeding. Finally, Publication of a re-examination certificate is announced in the Official Gazette.
PROCEEDINGS UNDER EX PARTE RE-EXAMINATION
Proceedings under ex parte re-examination system have been provided under 35 USC §301 – 35 USC §307.  Any person may file a request for re-examination by the USPTO, of any claim of a patent on the basis of any prior art cited in writing and accompanied by payment of an ex parte re-examination fee. The request must set forth the pertinency and manner of applying cited prior art to every claim for which re-examination is requested. After receiving a request for re-examination, the Director of USPTO (henceforth referred to as Director) sends a copy of the request to the owner of the patent, unless the requesting person himself is the owner of the patent. In ex parte re-examination procedure, at a written request of the person citing the prior art, his or her identity can be excluded from the official file of the patent and kept confidential.
Within three months following the filing of a request for re-examination, the Director determines whether a substantial new question of patentability, affecting any claim of the patent concerned, is raised by the request, with or without consideration of the prior art cited by the requestor or discovered by the Director on his own. In case the Director determines that there is no substantial new question of patentability raised, the determination is considered final and non appealable. If, however, the Director finds that a substantial new question of patentability affecting any claim of a patent is raised, the determination by the Director includes an order for re-examination of the patent. A record of the Director’s determination is placed in the official file of the patent, and a copy of the determination is sent to the owner of the patent and to the person requesting re-examination.
The patent owner is then provided a period of two months from the date of mailing of the Director’s determination to him, to file a statement, including any amendment to his patent and new claim or claims he may wish to propose, for consideration in the re-examination. However, no proposed, amended or new claim enlarging the scope of a claim of the patent is permitted in a re-examination proceeding. The patent owner is also required to serve a copy of his statement to the person who has requested re-examination. Subsequently, the requestor may file within a period of two months from the date of service; a reply to the statement filed by the patent owner and also serves the patent owner a copy of the reply filed.
After the time limits for filing the statement and reply have expired, reexamination is conducted by the Director. In any re-examination proceeding the patent owner is permitted to propose any amendment to his patent and a new claim or claims thereto, in order to distinguish the invention as claimed from the prior art cited. The patent owner involved in a re-examination proceeding may also appeal to the Board of Patent Appeals and Interferences (BPAI) with respect to any decision adverse to the patentability of any original or proposed amended or new claim of the patent. When the time for appeal has expired or any appeal proceeding has terminated, the Director issues and publishes a certificate canceling any claim of the patent finally determined to be unpatentable, confirming any claim of the patent determined to be patentable, and incorporating in the patent any proposed amended or new claim determined to be patentable.
PROCEEDINGS UNDER INTER PARTES RE-EXAMINATION
Proceedings under inter partes re-examination system have been provided under 35 USC §311 – 35 USC §318.  In a request for an inter partes re-examination, a third party is required to include in writing the identity of the real party in interest and set forth the pertinency and manner of applying cited prior art to every claim for which re-examination is requested, accompanied by payment of an inter partes re-examination fee. The Director after receipt of such a request sends a copy of the request to the owner of the patent.
Not later than 3 months after the filing of a request for inter partes reexamination, the Director determines whether a substantial new question of patentability affecting any claim of the patent concerned is raised by the request, with or without consideration of the prior art. In case the Director determines that there is no substantial new question of patentability raised, the determination is considered final and non-appealable. If however, the Director finds that a substantial new question of patentability affecting a claim of a patent is raised, the determination of the Director includes an order for inter partes re-examination of the patent. The order may be accompanied by the initial action of the USPTO on the merits of the inter partes re-examination conducted. A record of the Director’s determination is then placed in the official file of the patent, and a copy of the determination is mailed to the owner of the patent and to the third-party requester.
Once an order for inter partes re-examination of a patent has been issued, the patent owner may obtain a stay of any pending litigation which involves an issue of patentability of any claims of the patent which are the subject of the inter partes re-examination order.
In any inter partes re-examination proceeding, the patent owner is permitted to propose any amendment to the patent and a new claim or claims, except that no proposed amended or new claim enlarging the scope of the claims of the patent are permitted. With the exception of the inter partes re-examination request, any document filed by either the patent owner or the third-party requester is required to be served on the other party. In addition, the USPTO sends to the third-party requester a copy of any communication sent by the USPTO to the patent owner concerning the inter partes re-examination proceeding. Each time the patent owner files a response to an action on the merits of the patent from the USPTO, the third-party requester is provided one opportunity to file written comments addressing issues raised by the action of the USPTO or the patent owner’s response thereto.
The patent owner involved in an inter partes re-examination proceeding may appeal with respect to any decision adverse to the patentability of any original or proposed amended or new claim of the patent. Further, even the third-party requester may appeal with respect to any final decision favorable to the patentability of any original or proposed amended or new claim of the patent. In an inter partes re-examination proceeding, when the time for appeal has expired or any appeal proceeding has terminated, the Director issues and publishes a certificate canceling any claim of the patent finally determined to be unpatentable, confirming any claim of the patent determined to be patentable, and incorporating in the patent any proposed amended or new claim determined to be patentable.
ANALYSIS & CONCLUSION
The USPTO published on its web site its 21st Century Strategic Plan.  The plan includes a recommendation for Congress to establish “a patent review proceeding which would be instituted before, and handle by, the Board of Patent Appeals and Interferences.” The proposal would (1) “allow the public to cancel one or more claims in a patent within one year of its issue date;” and (2) “allow anyone threatened with a patent infringement suit to petition for a review within four months of being threatened.” The petitioner would be “required to make an initial showing of unpatentability otherwise the petition would be dismissed. If the showing found it sufficient, “fact-finding proceedings leading to a hearing by the Board on the merits” would follow. Both parties would be obliged to make mandatory disclosures of all relevant information. Under the proposal, the patent owner would have a single opportunity as of right to make a narrowing amendment of the challenged claims.
The USPTO views the proposal as offering a “less expensive alternative to district court litigation.” It would eliminate entirely the inter partes reexamination. Adverse decisions of the Board would be appealable to the Federal Circuits.
The strategic plan is a crucial step, as this concrete proposal of the USPTO establishes an administrative post-grant review of issued patents and hope that it will serve to lead a consensus supporting the enactment of necessary legislation.
The major challenge to the leading patent offices of the world is to keep pace with exponentially increasing workloads. The quality of granted patents should not be permitted to suffer as a result of increasing workloads or the inevitable move to patent inventions in new pioneering areas. Major patent offices of the world have established some form of post-grant review of granted patents, and these procedures have worked well. This will provide the recognized experts with an entirely new and effective capability to ensure that only truly deserving inventions receive their constitutional due. In turn, that will provide important assurances to the public on the quality of patent granted in a system in which anything under the sun created by humans can be patented.
Patents are provided as economic incentives for research and development and to facilitate and encourage disclosure of innovations so as to make it available in public domain. Laws providing for pre grant and post grant of patent are essential to prevent wrongful grant of patent. However, this has lead to undue delay in grant of patent, which has hit the main rationale behind incentive based patent system. There is a need to maintain the balance between the two, to ensure steady prosecution process and encourage research and development.
The main drawback of the post-grant opposition process in India is that this remedy is available only through the courts, making redressal a lengthy process and, in the case of bad patents, allowing the patent holder to enjoy a wrongful monopoly. This is of particular concern in India, given the protracted nature of the judicial process. 
Pre grant opposition on the other hand is more cost effective and result in faster disposal of cases on merits thereby reducing the costs incurred in contesting the post grant proceedings. Pre-grant oppositions could prevent the abuse of patent system by granting quality patents and avoid wasteful litigation at some later stage. An early stage patent opposition would only help the patent office to grant qualitative patents and reduce the burden of socio-economic costs of unwarranted grants. Its mechanism is faster as compared to post grant opposition where trials and extension of hearings occurs in a conventional manner which it happens in the Courts. Unlike post-grant opposition, there is no fee stipulated for filing a pre-grant opposition.
In United States, where a post-grant system is favoured studies have found that quality of patetns has been affected. According to the Federal Trade Commission, the US patents and trademarks offices have working under the assumption that “once an application has been filed, the claimed invention is effectively presumed to warrant a patent unless the PTO can otherwise. 
To conclude, the new two-stage patent opposition process has fuelled fears among innovator companies, particularly in the pharmaceutical industry. It will indeed be a challenge for India which is an emerging global economy to meet the commercial as well as legal challenges faced by the patent system of the country and become an attractive commercial destination for the foreign companies without violating any of its international obligations under the TRIPS Agreement.