List of Accounting firms issuing C5 attestations

PwC Germany (DEU)
www.pwc.de/en/digitale-transformation/bsi-c5-german-bsi-catalogue-of-requirements-for-more-transparency-in-the-cloud.html
EY (DEU)
www.ey.com/de_de/risk/attestation-certification-atc
Deloitte (DEU)
(updated 10.12.2024)
https://www.deloitte.com/de/de/services/audit/perspectives/bsi-c5-cloud-compliance.html
BDO Deutschland (DEU)
www.bdo.de/de-de/services/audit-assurance/it-controls-assurance/outsourcing-assurance
Rödl & Partner (DEU)
www.roedl.de/wen-wir-beraten/gesundheit-sozialwirtschaft/c5-testat
KPMG AG (DEU)
https://kpmg.com/de/de/home/themen/2024/03/das-digital-gesetz.html
TÜV Nord Group (DEU)
www.tuev-nord-group.com/en/newsroom/news/details/article/secure-cloud-computing-according-to-c5-tuevit-has-formed-a-partnership-with-fides-treuhand/
FIDES Treuhand GmbH & Co. KG (DEU)
www.fides-online.de/leistungen/c5/
HKKG (DEU)
hkkg-koeln.de/c5-pruefungen/
Simpliant (DEU)
https://simpliant.eu/de/services/c5-attestation
nbs partners audit GmbH Wirtschaftsprüfungsgesellschaft (DEU) (added 24.11.2024)
www.nbs-partners.de
IT AUDIT GmbH, Wirtschaftsprüfungsgesellschaft (DEU)
(added 3.12.2024)
www.it-audit.com
Dr. Stückmann und Partner mbB (DEU)
(added 2.2.2025)
www.stueckmann.de
Schellman (US)
www.schellman.com/blog/cloud-compliance/what-is-c5-attestation
Coalfire Controls LLC (US) https://coalfire.com/services/assessment/soc
Lazarus Alliance (US)
lazarusalliance.com/services/audit-compliance/c5/
Moss Adams LLP (US)
https://www.mossadams.com/articles/2020/11/c5-compliance-aids-data-transparency
A-Lign Assurance (Global)
https://www.a-lign.com/articles/c5-attestation

Accounting firms that issue C5 attestations

The listed firms claim to offer C5 attestations in the internet.