The BPO conducts formal and substantive examinations of invention patent applications. The BPO will complete the formality examination within 1 month from the filing date, and then the BPO will verify the Certified Priority Document and its related fees, and will conduct a preliminary substantive examination and unity examination of the patent application within 3 months after the end of the preliminary examination. A patent application that has paid the search fee and publication fee is published within 18 months from the filing date/priority date, and the opposition period is 3 months from the publication date. Search reports, written opinions on patentability and third-party opinions will be conveyed to the applicant no later than 6 months after the expiration of the 3-month opposition period. Can be authorized.
A 12-month novelty grace period is available if:
- The applicant authorizes others to use
 - manifest misuse by a third party
 
The initial protection period is 4 years, which can be extended for two consecutive three years, and the maximum protection period is 10 years.
- via Paris Convention : 12 months from earliest priority date.
 - via Nationalization of PCT : 31 months from earliest priority date.
 - Validation of European Patent in EPO member states: 3 months from the date of European patent grant
 
no
The BPO conducts formality examination of design patent applications.
20 years
Reinstatement of priority on grounds of "due care" and "unintentional/due care" accepted.
Bulgarian Patent and Trademark Office
English: Bulgarian Patent Office, abbreviation: BPO
Website: Патентното ведомство на Република България (bpo.bg)
Bulgarian Utility Model Patent Search: BPO Online - portal.bpo.bg
The BPO conducts formal and substantive examinations of invention patent applications. The BPO will complete the formality examination within 1 month from the filing date, and then the BPO will verify the Certified Priority Document and its related fees, and will conduct a preliminary substantive examination and unity examination of the patent application within 3 months after the end of the preliminary examination. A patent application that has paid the search fee and publication fee is published within 18 months from the filing date/priority date, and the opposition period is 3 months from the publication date. Search reports, written opinions on patentability and third-party opinions will be conveyed to the applicant no later than 6 months after the expiration of the 3-month opposition period. Can be authorized.
no