Shuichi Katsumata

*Please call me "Shu" for short. Pronounced exactly like "shoe".  


I'm a lead cryptography researcher at PQShield Ltd, U.K, working from Japan. I am also a collaborative researcher at the National Institute of Advanced Industrial Science and Technology (AIST), Japan. Before that, I was a senior cryptography researcher at AIST, Japan and a research consultant at PQShield Ltd, U.K.

My main research topics include, but are not limited to, lattice-based (or more generally post-quantum) cryptography. I enjoy constructing and providing security analysis of cryptographic primitives/protocols such as various types of signature and encryption schemes (e.g., ring/blind signatures, IBE/ABE), zero-knowledge proofs, and secure messaging protocols. 

I'm always thrilled, excited, and motivated to discuss any interesting problems with others so please feel free to reach out to me!!  

Also, PQShield is hiring so if you're interested either as a permanent researcher, post-doc, or intern, check out PQShield's career webpage or contact me directly. 

Contact: shuichi.katsumata [at] OR shuichi.katsumata000 [at]




International Conference


EUROCRYPT 2024. ePrint.

Real World Crypto 2024. (Contents from [KKPP20@ASIACRYPT] ePrint. + [HKKPW21@CCS] ePrint.)

PKC 2024. ePrint

FC 2024. Preproceeding.


ASIACRYPT 2023. ePrint.  

CRYPTO 2023. ePrint. video.

FC 2023. Proceeding

Real World Crypto 2023. video. (Contents from [HKP22@CCS]. ePrint.)


ACM CCS 2022. ePrint

CRYPTO 2022. ePrint.

EUROCRYPT 2022. ePrint


ACM CCS 2021. arXiv. video.

EUROCRYPT 2021. ePrint. video (by Ryo Nishimaki).

PKC 2021. ePrint. video (by Keitaro Hashimoto).


ASIACRYPT 2020. ePrint. video (by Shota Yamada).

ASIACRYPT 2020. ePrint. video (by Thomas Prest).

ASIACRYPT 2020. ePrint. video (by Federico  Pintore).

CRYPTO 2020. ePrint. video (by Takashi Yamakawa).

*(Historical Note: This is a major updated version of eprint:DKNYY18 with many new results, which itself is a merged version of eprint:DavNis18 and eprint:KatYam18.)

PETS/PoPETS 2020. Proceedings

EUROCRYPT 2020. ePrint. video (by Bogdan Ursu).

EUROCRYPT 2020. ePrint. video.

PKC 2020. ePrint. video (by Federico Pintore).


CRYPTO 2019. ePrint. video

ESORICS 2019. ePrint.

EUROCRYPT 2019. ePrint.

EUROCRYPT 2019. ePrint. video

PKC 2019. ePrint.

PKC 2019. ePrint.


ASIACRYPT 2018. (Invited to Journal of Cryptography.) ePrint.

ASIACRYPT 2018. ePrint.

PKC 2018. ePrint.

FC 2018. Preproceeding.


ASIACRYPT 2017. ePrint. video.

PST 2017. Proceedings.


ASIACRYPT 2016. ePrint. video


AISTATS 2015. Proceedings.


ProvSec 2014. Proceedings.

Journal Articles


Designs, Codes and Cryptography, 2023. Springer. To appear. (Full version of [BDKLP22@EC]

Designs, Codes and Cryptography, 2023. Springer


Journal of Cryptology, Volume 35, 2022. Springer. (Full version of [HKKP22@PKC]).

Theoretical Computer Science, Volume 900, 2022. Elsevier. (Full version of [EKW19@ESORICS]).


Journal of Cryptology, Volume 34, 2021. Springer. (Full version of [KYY18@AC]).


Theoretical Computer Science, Volume 809, 2020. Elsevier. (Full version of [KMT19@PKC]).


IEICE Transactions E101-D(11), 2018. (Full version of [HMKKH18@PST]).


IEICE Transactions E100-A(9), 2017. (Full version of [KK14@ProvSec]).




& Tsujii Shigeo Security Award, 2021.
- for the paper: An Efficient and Generic Construction for Signal’s Handshake (X3DH): Post-Quantum, State Leakage Secure, and Deniable. (with Keitaro Hashimoto, Kris Kwiatkowski,  Thomas Prest.)

& Tsujii Shigeo Security Award, 2018.
- for the paper: On the Untapped Potential of Encoding Predicates by Arithmetic Circuits and Their Applications

& Tsujii Shigeo Security Award, 2017.
- for the paper: Partitioning via Non-linear Polynomial Functions: More Compact IBEs from Ideal Lattices and Bilinear Maps. (with Shota Yamada.)