Signicent can conduct opposition searches for any patent office, the popular ones are summarized below:
European patent organisation (EPO)
Post Grant Opposition to any European patent granted by the European patent office (EPO) under the European Patent Convention (EPC) may be filed by any member of the public except for the proprietor himself. Such an opposition must be filed within 9 months of the publication of the mention that the patent ahs been granted. Generally, such opposition may lead to revocation of patent, rejection of opposition or may result to amendment of patet.
United States patent and trademark office (USPTO)
In US, the opposition proceeding is generally known as re-examination. Post grant review begins with a third party filling a petition after 9 months of the grant of the patent. Post Leahy-Smith America Invents Act (2011), any third party can challenge the validity of an issued patent using either post-grant review under 35 U.S.C. § 321 or inter partes review under 35 U.S.C. § 311.
Indian patent office (IPO)
Indian patent law allows two kinds of patent oppositions which include pre-grant patent opposition and post-grant patent opposition. The pre-grant opposition (under section 25(1) of Indian Patents Act 1970) acts as a check point on the validity of the patent which is under examination. On the other hand, post grant opposition (under section 25(2) of Indian Patents Act 1970) can be filed after 12 months from the date of publication of grant of patent. This kind of opposition is similar to USPTO or EPO.
Signicent can help you conduct prior art searches to find out most relevant pieces of prior arts which are pre-dated to the subject patent for a successful opposition proceeding. Such searches will be conducted on commercial patent, literature and market research databases in addition to open source databases.