Sigma Lithium — Regulatory Filings 2021

Jul 16, 2021

CERTIFICATE OF AUTHOR PORFÍRIO CABALEIRO RODRIGUEZ

I, Porfirio Cabaleiro Rodriguez, P.Eng., Ph.D., do hereby certify:

1. I am a Mining Engineer and Director for GE21 Consultoria Mineral, located at Avenida Afonso Pena, 3130 − 12º andar, Belo Horizonte, MG, Brazil, CEP 30.130-910.

2. This certificate applies to the Technical Report entitled “ Grota do Cirilo Lithium Project: Araçuaí and Itinga Regions, Minas Gerais, Brazil, Phase 2 (Barreiro) Update of the NI 43-101 Technical Report Feasibility Study ” with an effective date of June 2, 2021 (Technical Report).

3. I am a graduate in Mining Engineering from the Federal University of Minas Gerais, in Belo Horizonte, Brazil. I have worked as a Mining Engineer for more than 42 years.

4. I have read the definition of Qualified Person set out in the National Instrument 43-101 (NI 43-101) and certify that by reason of my education, affiliation with a professional association and past relevant work experiences, I fulfil the requirement to be an independent qualified person for the purposes of NI 43-101.

5. I have participated in the preparation of this Technical Report and am responsible for Sections 15, 16, 21.1, 21.2, 21.3, and the applicable parts of 1, 25 and 26.

6. I am independent of Sigma Lithium Corporation as defined by Section 1.5 of the Instrument. I do not have prior involvement with the properties that are the subject of the technical report.

7. As of the effective date of the Technical Report, to the best of my knowledge, information and belief, the sections of the technical report for which I am responsible contain all scientific and technical information that is required to be disclosed to make the technical report not misleading.

Signed and dated this July 15, 2021, at Belo Horizonte, Minas Gerais State.

“Signed and sealed” Porfirio Cabaleiro Rodriguez, BSc. (MEng), FAIG

Porfirio Cabaleiro Rodriguez, BSc. (MEng) Senior Director GE21, FAIG #3708