TIM S.A. (TIMB) backs 700 MHz auction bid and records key executive changes

Rhea-AI Filing Summary

TIM S.A. reported that its Board of Directors approved the company’s participation in all stages of the Brazilian National Telecommunications Agency (ANATEL) 700 MHz spectrum auction. The Board ratified all preparatory acts and broadly authorized officers and attorneys-in-fact to execute guarantees, submit bids, sign documents, and take all actions required to pursue licenses in this frequency band.

The Board also acknowledged the resignation of Legal Officer and Board Secretary Fabiane Reschke, effective March 31, 2026, leaving the Legal Officer position temporarily vacant. The remaining statutory executive officers were confirmed in their roles, and Leonardo Caiaffo Ferreira was elected Secretary of the Board of Directors, with his mandate running until the first Board meeting after the 2027 Annual Shareholders’ Meeting.

Key Figures

Board meeting date: April 14, 2026 Executive resignation date: March 31, 2026 Mandate horizon: 2027 +1 more

4 metrics

Board meeting date April 14, 2026 Date of TIM S.A. Board of Directors’ meeting approving 700 MHz participation

Executive resignation date March 31, 2026 Effective date of Fabiane Reschke’s resignation as Legal Officer and Board Secretary

Mandate horizon 2027 Officers and Board Secretary serve until first Board meeting after 2027 Annual Shareholders’ Meeting

Frequency band 700 MHz Spectrum band covered by ANATEL auction TIM S.A. plans to join

Key Terms

700 MHz Auction, Brazilian National Telecommunications Agency - ANATEL, Request for Proposals, Statutory Executive Board, +1 more

5 terms

700 MHz Auction financial

"participation in the auction related to the 700 MHz frequency band (the ‘700 MHz Auction’)"

Brazilian National Telecommunications Agency - ANATEL regulatory

"to be conducted by the Brazilian National Telecommunications Agency - ANATEL"

Request for Proposals regulatory

"in accordance with the Request for Proposals approved and published by the Brazilian National Telecommunications Agency – ANATEL"

A request for proposals (RFP) is a formal, written invitation a company or government issues when it wants outside firms to bid on supplying goods, services, or projects; think of it as advertising a job and asking qualified vendors to submit detailed offers. For investors, an RFP matters because it signals potential new revenue, shifts in costs, or changes in competitive position—winning a large RFP can boost future sales, while losing or delayed awards can create execution risk.

Statutory Executive Board financial

"Accordingly, the Company’s Statutory Executive Board shall be composed of the following officers"

Authorization Terms regulatory

"and (xv) executing Authorization Terms, in summary, performing any and all acts related to the 700 MHz Auction"

Form 6-K: How Foreign Companies Report to the SEC →

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER
PURSUANT TO RULE 13a-16 OR 15d-16
UNDER THE SECURITIES EXCHANGE ACT OF 1934

Date of Report: April 14, 2026

Commission File Number: 001-39570

TIM S.A.
(Exact name of Registrant as specified in its Charter)

João Cabral de Melo Neto Avenue, 850 – North Tower – 12^th floor
22775-057 Rio de Janeiro, RJ, Brazil
(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F ☒ Form 40-F ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1).

Yes ☐ No ☒

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7).

Yes ☐ No ☒

 

TIM S.A.

Publicly-Held Company

CNPJ/MF 02.421.421/0001-11

NIRE 33.3.0032463-1

MINUTES OF THE BOARD OF DIRECTORS’ MEETING

HELD ON APRIL 14, 2026

DATE, TIME AND PLACE: April 14, 2026, at 12.00 p.m., at the head office of TIM S.A. (“Company”), domiciled at Avenida João Cabral de Mello Neto, 850, Torre Sul, 13° floor, Barra da Tijuca, in the city and State of Rio de Janeiro.

PRESENCE: The Board of Directors’ Meeting of the Company was held at the date, time and place mentioned above, with the presence of Messrs. Adrian Calaza, Alberto Mario Griselli, Alessandra Michelini, Camillo Greco, Claudio Giovanni Ezio Ongaro, Denísio Augusto Liberato Delfino, Flavia Maria Bittencourt, Gesner José de Oliveira Filho, Gigliola Bonino and Leonardo de Carvalho Capdeville, either in person or by means of audio or videoconference, as provided in the 2^nd paragraph of Section 25, of the Company’s By-laws.

BOARD: Mr. Adrian Calaza – Chairman; and Mr. Leonardo Caiaffo Ferreira – Secretary.

AGENDA: Presentation on the general conditions for the Company’s participation in the 700 MHz spectrum auction to be conducted by the Brazilian National Telecommunications Agency - ANATEL.

RESOLUTIONS: Upon review of the materials presented and filed at the Company’s head office, and based on the information provided and the discussions held on the matter included in the Agenda, the Board Members, by the unanimous vote of those present and with the abstention of those legally prevented from voting, resolved to record their statements and resolutions as follows:

The Board members acknowledged the general terms and conditions for the Company’s participation in the auction related to the 700 MHz frequency band (the ‘700 MHz Auction’) and approved the Company’s participation in all stages of such bidding process, in accordance with the Request for Proposals approved and published by the Brazilian National Telecommunications Agency – ANATEL (‘ANATEL’).

CONT. OF MINUTES OF THE BOARD OF DIRECTORS’ MEETING OF TIM S.A.

April 14, 2026

Accordingly, the Board Members, in accordance with the terms and criteria set forth in the supporting materials, ratified all preparatory acts carried out up to the present date in connection with the 700 MHz Auction and authorized the Company’s officers and/or attorneys-in-fact, acting individually or jointly, to take all necessary actions, execute any instruments, agreements, contracts and terms, and provide any representations and warranties required for the due implementation of this resolution, including, but not limited to: (i) contracting bid maintenance and performance guarantees in any of the forms permitted under the 700 MHz Auction, including bank guarantee letters, performance bonds or cash collateral; (ii) submitting proposals and performing any other acts related to the Company’s participation in the 700 MHz Auction; (iii) subsequently obtaining the authorizations for the use of radiofrequencies resulting therefrom, in the form and on the dates designated by ANATEL; (iv) preparing, executing, submitting and renewing price proposals, including substitute proposals, and submitting bids; (v) submitting identification, tax compliance and qualification documents; (vi) issuing receipts; (vii) initialing envelopes and documents; (viii) executing attendance lists and minutes; (ix) issuing and executing statements; (x) submitting challenges and petitions; (xi) waiving appeal deadlines; (xii) filing appeals and requests for reconsideration, as well as contesting them; (xiii) granting and receiving guarantees; (xiv) taking the measures necessary for the definition and indication of locations related to the assumption of commitments; and (xv) executing Authorization Terms, in summary, performing any and all acts related to the 700 MHz Auction and to the granting of authorizations for the use of radiofrequencies arising therefrom.

In addition to the matter included on the Agenda, the Board Members recorded their resolutions regarding the following off-agenda matters, as described below:

The Board Members acknowledged the resignation letter submitted by Mrs. Fabiane Reschke on March 31, 2026, with immediate effect, in respect of the positions she held at the Company as Diretora Jurídica (Legal Officer) and Secretary of the Board of Directors. The members of the Board of Directors thanked Mrs. Fabiane Reschke for her commitment and dedication in the performance of her duties throughout her term of office and wished her success in her new endeavors.

The position of Diretor Jurídico (Legal Officer) remains vacant until her replacement is duly elected and takes office. Accordingly, the Company’s Statutory Executive Board shall be composed of the following officers: (i) Alberto Mario Griselli, Diretor Presidente (Chief Executive Officer); (ii) Andréa Palma Viegas Marques, Diretora Financeira (Chief Financial Officer); (iii) Vicente de Moraes Ferreira, Investor Relations Officer; (iv) Mario Girasole, Regulatory and Institutional Affairs Officer; and (v) Maria Antonietta Russo, People, Culture & Organization Officer.

The Company’s Executive Officers shall hold office until the first meeting of the Board of Directors to be held after the Company’s Annual Shareholders’ Meeting scheduled for 2027, with their terms being extended, if necessary, until their duly elected successors take office.

CONT. OF MINUTES OF THE BOARD OF DIRECTORS’ MEETING OF TIM S.A.

April 14, 2026

Finally, the Board of Directors, in accordance with its Internal Regulations, nominated and elected Mr. Leonardo Caiaffo Ferreira to serve as Secretary of the Company’s Board of Directors, until the first meeting of the Board of Directors to be held after the Company’s Annual Shareholders’ Meeting in 2027.

CLOSING: With no further issues to discuss, the meeting was adjourned, and these minutes drafted as summary, read, approved and signed by all attendees Board Members.

I herein certify that these minutes are the faithful copy of the original version duly recorded in the respective corporate book.

Rio de Janeiro (RJ), April 14, 2026.

LEONARDO CAIAFFO FERREIRA

Secretary

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

		TIM S.A.
Date: April 14, 2026		By:	/s/ Alberto Mario Griselli
			Alberto Mario Griselli
			Chief Executive Officer, Chief Financial Officer and Investor Relations Officer

FAQ

What did TIMB’s Board approve regarding the 700 MHz spectrum auction?

TIM S.A.’s Board approved the company’s participation in all stages of ANATEL’s 700 MHz spectrum auction. Directors ratified all preparatory acts and authorized officers to submit bids, provide guarantees, sign contracts, and complete all necessary steps to obtain related radiofrequency use authorizations.

Which regulator is overseeing TIMB’s 700 MHz auction process?

The 700 MHz spectrum auction involving TIM S.A. is overseen by the Brazilian National Telecommunications Agency, ANATEL. The Board’s approval specifically references compliance with ANATEL’s Request for Proposals and related procedures for granting authorizations to use radiofrequencies in this band.

Which executive resigned from TIMB and which positions were affected?

TIM S.A. recorded the resignation of Fabiane Reschke, effective March 31, 2026. She stepped down from the roles of Legal Officer (Diretora Jurídica) and Secretary of the Board of Directors. The Board expressed thanks for her service and noted that the Legal Officer position remains vacant pending a successor.

Who currently makes up TIMB’s Statutory Executive Board after this 6-K?

After the changes, TIM S.A.’s Statutory Executive Board comprises Alberto Mario Griselli as Chief Executive Officer, Andréa Palma Viegas Marques as Chief Financial Officer, Vicente de Moraes Ferreira as Investor Relations Officer, Mario Girasole as Regulatory and Institutional Affairs Officer, and Maria Antonietta Russo as People, Culture & Organization Officer.

Until when will TIMB’s current executive officers and Board Secretary serve?

TIM S.A. states that its executive officers will serve until the first Board meeting following the 2027 Annual Shareholders’ Meeting. The newly elected Board Secretary, Leonardo Caiaffo Ferreira, will serve under the same timeline, or until successors are duly elected and take office.

What authority did TIMB’s Board grant management for the 700 MHz Auction?

TIM S.A.’s Board authorized officers and attorneys-in-fact to take wide-ranging actions for the 700 MHz Auction. This includes arranging bid and performance guarantees, submitting and revising proposals, filing appeals or waivers, handling documentation, and executing Authorization Terms related to radiofrequency use.