WIPO - PCT Applicant's Guide BG - Bulgaria
Patent Office of the Republic of Bulgaria

    Applicable as from 29 August 2025
    (published on 29 August 2025)

    Summary of latest changes in this version
    GENERAL INFO: Means of telecommunication (In force since 20 October 2023)
    RO: Agent (In force since 27 October 2020)
    The procedure in the national Phase: Various (In force since 27 October 2020)
    List of changes

    Advance notice: The Office has notified the IB of changes entering into force soon; you can already consult the changes that will be effective 1 Jan 2026.
    All available versions

    Useful information

    The PCT Applicant’s Guide is updated almost every week with information received by the International Bureau.
    In case of question, please contact the Office or the International Bureau: pct.guide@wipo.int.
    List of abbreviations used in this document:
    Office: Patent Office of the Republic of Bulgaria
    BGL: Bulgarian Law Patent
    List of currencies used in this document:
    BGN (Bulgarian lev), EUR (Euro)
    Countries and Offices information:
    The list of acronyms used for Offices is no longer shown as it has been integrated in the mouseover functionality for each ST.3 code shown in this document.
    Refer to List of WIPO Standards, Recommendations and Guidelines formerly Annex K, List of country names and two-letter codes. It includes a list of short names and two-letter codes accepted for use in indicating States, other entities and intergovernmental organizations and their Offices in documents relating to international applications under the PCT. The list is as set out in WIPO Standard ST.3.
    Also refer to PCT Contracting States formerly Annex A.
    Office profile
    For more technical information about the Office, refer to ePCT Office profile.
    PCT Reservations, Declarations, Notifications and Incompatibilities
    The Office does not have any reservations, declarations, notifications or incompatibilities.
    Refer to the full list.
    Office Closed dates
    The Office is closed weekly on Saturday and Sunday
    Additional closed dates can be consulted on the Office Closed dates page

    International Phase

    Annex B - Information on Contracting States or Intergovernmental Organization

    Contracting State:
    Bulgaria
    Two-letter code:
    BG
    Name of Office:
    Patent Office of the Republic of Bulgaria
    Location:
    52B Dr. G.M. Dimitrov Blvd.
    1040 Sofia
    Bulgaria
    Mailing address:
    Same as above
    Telephone:
    (359-2) 970 13 21
    E-mail:
    services@bpo.bg
    Website:
    Facsimile:
    (359-2) 873 52 58
    Does the Office accept the filing of documents by facsimile or the like means (PCT Rule 92.4)?
    Yes, by facsimile
    Which kinds of documents may be so transmitted?
    All kinds of documents
    Must the original of the document be furnished in all cases?
    Yes, within 14 days from the date of the transmission
    Does the Office send notifications via e-mail in respect of international applications?
    Yes
    Would the Office accept evidence of mailing a document, in case of loss or delay, where a delivery service other than the postal authorities is used (PCT Rule 82.1)?
    No
    Is the Office prepared to allow applicants to make applications available to the WIPO Digital Access Service for Priority Documents (DAS) (PCT Rule 17.1(b-bis)?
    More information about WIPO DAS is available at: https://www.wipo.int/en/web/das.
    No
    Competent receiving Office(s) for international applications filed by nationals or residents of this State:
    A resident of Bulgaria may file an international application directly with the European Patent Office or with the International Bureau of WIPO three months after an application for a patent for the same invention has been filed at the Patent Office of the Republic of Bulgaria and the latter application has been classified by the defense authorities of Bulgaria as not being of a confidential nature
    BG,
    EP,
    IB
    Does national legislation restrict the filing of international applications with foreign Offices?
    Refer to the Office
    Competent designated (or elected) Office(s) for this State:
    National protection: BG
    European patent: EP
    Types of protection available via the PCT:
    National:
    Patents,
    Utility models (a utility model may be sought instead of or in parallel with a national patent)
    European:
    Patents
    Payment methods accepted by the Office:
    Refer to the Office
    Availability under the national law for an international-type search (PCT Article 15):
    Article 68(2) of the Law on Patents and Utility Model Registration
    Provisional protection after international publication:
    Where the designation is made for the purposes of a national patent:
    The international application made available to the public shall obtain temporary protection, under paragraphs (1) and (2) of PCT Article 29, as from the day on which the issue of the Official Bulletin of the Patent Office of the Republic of Bulgaria containing the announcement of the publication of the Bulgarian translation of the international application has come out.
    Where the designation is made for the purposes of a European patent:
    The European application made available to the public shall obtain temporary protection under Art. 67(1) of the European Patent Convention, as from the day of publication of the issue of the Official Bulletin of the Patent Office of the Republic of Bulgaria containing the announcement of the publication of the Bulgarian translation of the European application (refer to Art. 72b(3) of the Law on Patents and Utility Model Registration).
    Information of interest if this Contracting State is designated (or elected)
    For national protection
    Time when the name and address of the inventor must be given:
    May be in the request or may be furnished later. If not already complied with within the time limit applicable under PCT Article 22 or 39(1), the Office will invite the applicant to comply with the requirement within three months from the date of invitation.
    Are there special provisions concerning the deposit of microorganisms and other biological material?
    Yes, refer to Annex L.
    For a European patent
    Refer to Annex B(EP)

    Annex C - Receiving Office

    Competent receiving Office for nationals and residents of:
    Bulgaria
    Language in which international applications may be filed:
    If the language in which the international application is filed is not accepted by the International Searching Authority (refer to Annex D), the applicant will have to furnish a translation (PCT Rule 12.3).
    Bulgarian,
    English,
    Russian
    Language accepted for language-dependent free text in the sequence listing:
    Same language as the international application (Bulgarian, English or Russian)
    Language in which the request may be filed:
    English,
    Russian
    Number of copies required by the receiving Office if the international application is filed on paper:
    3
    Does the receiving Office accept the filing of international applications in electronic form?
    Where the international application is filed in electronic form in accordance with and to the extent provided for in Part 7 and Annex F of the Administrative Instructions, the total amount of the international filing fee is reduced (refer to “Fees payable to the RO”).
    Where the international application contains a sequence listing as a separate part of the description, this must be furnished in accordance with Annex C of the Administrative Instructions, that is, in compliance with WIPO Standard ST.26 XML format; no fees are due for sequence listings filed in this format.
    For the relevant notifications by the Office, refer to the Official Notices (PCT Gazette) dated 3 December 2020, page 269, 4 August 2022, page 205 and 5 October 2023, page 186.
    Yes, the Office accepts electronic filing via ePCT-Filing
    Does the receiving Office accept the submission of pre-conversion documents and, if yes, in which format (Section 706 of the PCT Administrative Instructions)?
    Yes, any format
    Does the receiving Office accept incorporation by reference (PCT Rule 20.6)?
    Yes
    Does the receiving Office accept the submission of color drawings on an informal basis and transmit them to the International Bureau?
    Yes
    Does the receiving Office accept requests for restoration of the right of priority (PCT Rule 26bis.3)?
    Yes,
    the Office applies both the “unintentional” and the “due care” criteria to such requests
    Competent International Searching Authority:
    EP,
    RU
    Competent International Preliminary Examining Authority:
    RU

    EP
    The Office is competent only if the international search is or has been carried out by that Office.
    Fees payable to the RO:
    Transmittal fee:
    80 BGN
    International filing fee:
    This fee is reduced by 90% if certain conditions apply (refer to Annex C(IB)).
    1,417 EUR
    Fee per sheet in excess of 30:
    This fee is reduced by 90% if certain conditions apply (refer to Annex C(IB)).
    16 EUR
    Reductions (under Schedule of Fees, item 4):
    Electronic filing (the request in character coded format):
    213 EUR
    Electronic filing (the request, description, claims and abstract in character coded format):
    320 EUR
    Search fee:
    Refer to
    Annex D(EP)
    Annex D(RU)
    Fee for priority document (PCT Rule 17.1(b)):
    None
    Fee for requesting restoration of the right of priority (PCT Rule 26bis.3(d)):
    None
    Is an agent required by the receiving Office?
    No, if the applicant resides in Bulgaria, in another member State of the European Union, in another State party to the Agreement on the European Economic Area, or in Switzerland
    Yes, if the applicant is a non-resident
    Who can act as agent?
    Any patent attorney or patent agent registered to practice before the Office
    Waiver of power of attorney:
    Has the Office waived the requirement that a separate power of attorney be submitted?
    Refer to the Office
    Has the Office waived the requirement that a copy of a general power of attorney be submitted?
    Refer to the Office

    Annex L - Deposits of Microorganisms and Other Biological Material

    Requirements of designated and elected Offices
    Only Offices whose applicable national law contains provisions concerning the deposits of microorganisms and other biological material are listed in Annex L. Unless otherwise indicated, deposits may be made for the purposes of patent procedure before these Offices with any depositary institution having acquired the status of international depositary authority under the Budapest Treaty on the International Recognition of the Deposit of Microorganisms for the Purposes of Patent Procedure.
    For a list of these institutions refer to:
    http://www.wipo.int/treaties/en/registration/budapest/pdf/idalist.pdf (and the detailed requirements for each institution at: https://www.wipo.int/budapest/en/guide/section_d/subsection_c.html)
    Notifications related thereto may be consulted under:
    http://www.wipo.int/treaties/en/registration/budapest/
    Further information concerning the requirements of international depository authorities under the Budapest Treaty is available at:
    http://www.wipo.int/budapest/en/guide/index.html
    Time (if any) earlier than 16 months from priority date by which applicant must furnish:
    — the indications prescribed in Rule 13bis.3(a)(i) to (iii):
    At the time of filing, either in the description or separately
    — any additional indications:
    At the time of filing (as part of the application)
    Additional indications (if any) which must be given besides those prescribed in Rule 13bis.3(a)(i) to (iii) pursuant to notifications from the Office:
    To the extent available to the applicant, relevant information on the characteristics of the microorganism

    National Phase

    Summary of requirements for entry into the national phase

    Time limits applicable for entry into the national phase:
    Under PCT Article 22(3): 31 months from the priority date
    Under PCT Article 39(1)(b): 31 months from the priority date
    Does the Office permit reinstatement of rights (PCT Rule 49.6)?
    Yes, the Office permits reinstatement of rights under the “due care" criterion.
    Translation of international application required into (one of) the following language(s):
    If not already complied with within the time limit applicable under PCT Article 22 or 39(1), the Office will invite the applicant to furnish a complete translation within three months from the date of the invitation.
    Bulgarian
    Required contents of the translation for entry into the national phase:
    If not already complied with within the time limit applicable under PCT Article 22 or 39(1), the Office will invite the applicant to furnish a complete translation within three months from the date of the invitation.
    Under PCT Article 22: Description, claims (if amended, both as originally filed and as amended, together with any statement under PCT Article 19), any text matter of drawings, abstract
    Under PCT Article 39(1): Description, claims, any text matter of drawings, abstract (if any of those parts has been amended, both as originally filed and as amended by the annexes to the international preliminary examination report)
    Is a copy of the international application required in particular circumstances?
    No
    Does the Office accept color drawings under its national law?
    Refer to the Office
    National fees:
    Patents
    Filing fee
    This fee must be paid within the time limit applicable under PCT Article 22 or 39(1).
    40 BGN
    Publication fee
    70 BGN
    Utility models
    Filing fee
    This fee must be paid within the time limit applicable under PCT Article 22 or 39(1).
    40 BGN
    Exemptions, reductions or refunds of fees:
    For patents and utility models:
    The filing fee is reduced by 50% where the applicant is the inventor, a State educational institution, an academic research organization, a budgetary organization or a small or medium-sized enterprise
    Special requirements of the Office (PCT Rule 51bis):
    If not already complied with within the time limit applicable under PCT Article 22 or 39(1), the Office will invite the applicant to comply with the requirements within a time limit fixed in the invitation.
    Instrument of assignment of the priority right if the applicants are not identical
    This requirement may be satisfied if the corresponding declaration has been made in accordance with PCT Rule 4.17.
    Instrument of assignment of the international application if the applicant has changed after the international filing date
    Declaration concerning the inventorship
    This requirement may be satisfied if the corresponding declaration has been made in accordance with PCT Rule 4.17.
    Appointment of an agent if the applicant is not resident in Bulgaria
    Translation of the international application to be furnished in three copies
    Who can act as agent?
    Any patent attorney or patent agent registered to practice before the Office
    Does the Office accept the effect of restoration of the right of priority by the receiving Office (PCT Rule 49ter.1)?
    Yes
    Does the Office accept requests for restoration of the right of priority (PCT Rule 49ter.2)?
    Yes,
    the Office applies both the “unintentional” and the “due care” criteria to such requests

    The procedure in the national Phase

    BG.01 TRANSLATION (CORRECTION)
    BGL Art. 35(3)
    Errors in the translation of the international application can be corrected with reference to the text of the international application as filed (refer to National Phase, paragraphs NP 6.002 and NP 6.003).
    BG.02 LANGUAGE OF PROCEEDINGS
    BGL Art. 34(2),
    BGL Art. 35(3)

    The language of proceedings is Bulgarian.
    BG.03 FEES (MANNER OF PAYMENT)
    BGL Art. 5(2)
    The manner of payment of the fees indicated in the Summary and in this Chapter is outlined in Annex BG.I. The amount of fees for patents is reduced by 50% in case of a declaration of readiness for licensing made by the applicant at the time of entering the national phase.
    BG.04 CLAIMS FEE
    The claims fee must be computed on the basis of the number of claims valid at the beginning of the national phase (that is, where amendments have been filed, the claims as amended under PCT Article 19 or 34(2) or the claims as submitted by the applicant under PCT Article 28 or 41 upon entering the national phase). Where the applicant fails to pay the correct amount of the claims fee, the Office will invite him to pay the missing amount.
    BG.05 DECLARATION CONCERNING THE INVENTOR
    BGL Art. 36
    The applicant must state who the inventor is and give his name and nationality. This declaration will be made on behalf of the applicant by his agent.
    BG.06 POWER OF ATTORNEY
    BGL Art. 3(2)
    An agent must be appointed by filing a power of attorney. The model is given in Annex BG.II.
    BG.07 EXAMINATION
    BGL Art. 35(2),
    BGL Art. 46(1)

    The Office carries out a formal requirements examination, preliminary examination and admissibility. Entering the national phase, the applicant must file a request and pay a filing fee, a fee for formality requirements examination, a fee for preliminary examination and admissibility for publication of the application, a search and examination fee, a fee for claims and a fee for claimed priorities. The Office invites the applicant to pay the fees within three months from the filing day. Where the applicant fails to furnish the document certifying payment of fees within the term in the invitation, the application shall be deemed to be withdrawn. If the result of the examination shows that the application contains formal defects or is not otherwise patentable, the Office invites the applicant to submit corrections and/or amendments. The manner of payment of the fees indicated in the Summary and in this Chapter is outlined in Annex BG.I.
    BG.08 PUBLICATION
    BGL Art. 46c
    The application is published in Bulgarian after the expiry of 18 months from the filing date or the priority date.
    BG.09 EXAMINATION FEE WHERE AN ADDITIONAL SEARCH HAS TO BE CARRIED OUT
    BGL Art. 69(4)
    This fee is to be paid where the priority claim(s) is (are) cancelled or where the international search has not been carried out for a part of the international application because of lack of unity.
    BG.10 FEES FOR GRANT AND PUBLICATION
    BGL Art. 53
    A fee for grant, a fee for mention of the grant of a patent in the Official Bulletin of the Office and a fee for publication of the granted patent must be paid within three months after receipt by the applicant of the invitation to pay said fees. The amounts of the fees are indicated in Annex BG.I.
    BG.11 ANNUAL FEES
    BGL Art. 33,
    BGL Art. 26(2),
    BGL Art. 53

    After a patent has been granted, a fee must be paid for each year following the international filing date. Payment of the annual fees, for the years which have expired or begun on the date of granting of the patent, must be made together with the fees for grant and publication of the patent, within three months from the receipt of an invitation to pay said fees, in accordance with Article 53. Where the current patent year expires with the said three month term, the fee for the next “patent year” shall also be paid. The annual fees for subsequent years must be paid not later than the last day of the month in which the preceding “patent year” expires. Where the applicant fails to pay by that day, payment can still be made, together with a 100% surcharge for late payment, within six months from the due date. A patent which has lapsed due to failure to pay the fee may be renewed within a six-month period after payment of the patent renewal fee. The “patent years” are counted from the international filing date. The amounts of the annual fees are indicated in Annex BG.I.
    BG.12 AMENDMENT OF THE APPLICATION; TIME LIMITS
    PCT Article 28,
    PCT Article 41,
    BGL Art. 42,
    BGL Art. 46(1)

    The applicant may make, without changing the substance of the invention, amendments or corrections to the description, claims or drawing(s) within one month from the fulfillment of the requirements under PCT Article 22 or 39(l). Further amendments may be made up to the grant of the patent where required by the Office, provided that the scope of the subject matter of the application is not broadened thereby.
    BG.13 REVIEW UNDER ARTICLE 25 OF THE PCT
    PCT Article 25,
    PCT Rule 51,
    BGL Art. 71

    The applicable procedure is outlined in paragraphs NP 6.018 to NP 6.021 of the National Phase. If, upon review under PCT Article 25, the Office denies an error or omission on the part of the receiving Office or the International Bureau, a reasoned appeal against this decision may be lodged with the Office within three months from the date of receipt of the decision. The decision of the Office on the appeal is final.
    BG.14 EXCUSE OF DELAYS IN MEETING TIME LIMITS
    PCT Article 24(2),
    PCT Article 48(2),
    BGL Art. 49

    Reference is made to paragraphs NP 6.022 to NP 6.027 of the National Phase.
    BG.15
    Reinstatement may be requested where the applicant, in spite of all due care reasonably required, was unable to observe a time limit during the international phase or before the Office, default of which is prejudicial to his rights. The request shall be submitted within one month after the reason for missing the deadline has lapsed, but not later than three months after the expiration of the missed deadline. The request for reinstatement must be presented in writing, state the grounds on which it is based and set out the facts on which it relies.
    BG.16 EXTENSION OF TIME LIMIT FOR REPLY TO OFFICIAL ACTIONS
    BGL Art. 48
    Whenever the applicant cannot reply to official actions in due time he may be granted an extension by three months by filing with the Office a special request (no prescribed form) and paying a fee as indicated in Annex BG.I. Such extension may be requested not more than twice.
    BG.17 UTILITY MODEL
    PCT Rule 49bis.1,
    PCT Rule 49bis.1(a),
    PCT Rule 49bis.1(b),
    PCT Rule 76.5,
    BGL Art. 73,
    BGL Art. 74,
    BGL Art. 75,
    BGL Art. 75b,
    BGL Art. 75d

    Legal protection for utility models shall be granted through registration with the Office. The registration shall have effect with respect to third parties as of the date of publication in the Official Bulletin of the Office. The term of validity of a utility model registration shall be four years as of the filing date of the application. It may be extended by two consecutive three-year periods. The total term of validity may not exceed 10 years as of the filing date of the application. Where the applicant wishes to obtain a utility model registration on the basis of an international application, instead of a patent or in addition to a patent, or in the cases referred in Article 71, he must file a request for transformation and he shall pay a filing fee and a fee for examination of the formal requirements. The Office invites the applicant to pay the fees within one month from the filing day. Where the applicant fails to pay the correct amount of the fees, the examination department will invite him to pay the missing amount. Where the applicant fails to furnish the document certifying payment of fees within the time limit fixed in the invitation, the application shall be deemed to be withdrawn. The amounts of the filing fee and the fee for examination of the formal requirements are indicated in Annex BG.I.
    The applicant of a patent application may also file an application for utility model registration for the same invention, subject to the provisions of Article 73(5), invoking the filing date and the priority date of the patent application.
    BG.18 CONVERSION
    BGL Art. 47a
    Up to the grant of a patent an application for a patent may be converted into an application for a utility model registration.

    Annexes

    Annex BG.I - Fees
    Patents
    Filing fee
    The application, examination and appeal fees are reduced by 50% where the applicant is the inventor, a State educational institution, an academic research organization, a budgetary organization or a small or medium-sized enterprise.
    40 BGN
    Fee for publication of the application
    70 BGN
    Examination fee:
    The application, examination and appeal fees are reduced by 50% where the applicant is the inventor, a State educational institution, an academic research organization, a budgetary organization or a small or medium-sized enterprise.
    — for one invention
    180 BGN
    — for a group of inventions
    180 BGN
    Claims fee for each claim in excess of 10
    0 BGN
    Fee for priority claims
    per priority 20 BGN
    Fee for grant
    70 BGN
    Fee for publication of the patent:
    — for the patent specification, claims and drawings:
    — up to 10 pages
    80 BGN
    — for each page in excess of 10
    10 BGN
    Fee for publication of the granted patent (independent claims included)
    50 BGN
    Appeal fee against:
    The application, examination and appeal fees are reduced by 50% where the applicant is the inventor, a State educational institution, an academic research organization, a budgetary organization or a small or medium-sized enterprise.
    (a) a decision to fully or partially refuse the grant of a patent:
    — for one invention
    180 BGN
    — for a group of two inventions
    280 BGN
    (b) a decision to terminate the application proceedings
    90 BGN
    Annual fees:
    — for the 1st to 3rd year
    per year 40 BGN
    — for the 4th year
    40 BGN
    — for the 5th year
    140 BGN
    — for the 6th year
    180 BGN
    — for the 7th year
    220 BGN
    — for the 8th year
    270 BGN
    — for the 9th year
    380 BGN
    — for the 10th year
    500 BGN
    — for the 11th year
    600 BGN
    — for the 12th year
    700 BGN
    — for the 13th year
    800 BGN
    — for the 14th year
    900 BGN
    — for the 15th year
    1,000 BGN
    — for the 16th year
    1,100 BGN
    — for the 17th year
    1,200 BGN
    — for the 18th year
    1,300 BGN
    — for the 19th year
    1,500 BGN
    — for the 20th year
    1,700 BGN
    Renewal fee
    450 BGN
    Other fees:
    Publication of patent description, claims or abstract in the Official Bulletin:
    — up to 10 pages
    80 BGN
    — for each page after the 10th
    10 BGN
    Utility models
    Filing fee
    The application, examination and appeal fees are reduced by 50% where the applicant is the inventor, a State educational institution, an academic research organization, a budgetary organization or a small or medium-sized enterprise.
    40 BGN
    Fee for priority claims
    per priority 20 BGN
    Examination fee
    The application, examination and appeal fees are reduced by 50% where the applicant is the inventor, a State educational institution, an academic research organization, a budgetary organization or a small or medium-sized enterprise.
    180 BGN
    Registration fee
    80 BGN
    Fee for grant
    45 BGN
    Appeal fee against:
    (a) a decision to fully or partially refuse the registration of a utility model
    140 BGN
    (b) a decision to suspend the registration proceedings
    90 BGN
    Other fees:
    Publication in the Official Bulletin of independent claims for registered utility models
    50 BGN
    Extension of registration terms for utility models
    50 BGN
    — for the 5th to the 7th year
    300 BGN
    — for the 8th to the 10h year
    400 BGN
    How can payment of fees be effected?
    All payments of fees must be effected by the applicants to the Patent Office of the Republic of Bulgaria in Bulgarian leva to the :
    Bulgarian National Bank–Central Office
    IBAN
    BG90 BNBG 9661 3100170901
    BIC
    BNBGBGSD
    Fees paid to this account are regarded as being received by the Office at the date on which the Bulgarian National Bank credits the money to the account of the Office
    Forms
    The following documents are maintained by the Office. Refer to the Office website (Annex B) for latest version and other languages.
    Annex BG.II - Declaration concerning the identity of the inventor
    Annex BG.III - Power of attorney
    Current version applicable from 29 Aug 2025 , printed on 19 Oct 2025
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