Accepted paper is:

Beholder Signatures
Authors: Stefan Dziembowski, Sebastian Faust, Pawel Kedzior, Marcin Mielniczuk, Susil Kumar Mohanty, Krzysztof Pietrzak
Digital signatures usually only confirm that someone holds a secret key. They do not guarantee that this person actually knows the full signed message. Several people could split the key and the message between them and jointly create the signature using secure multi-party computation. In this technique, multiple computers compute together without revealing their secret inputs to each other. This way, a signature could be produced without anyone knowing the complete message. In the paper, the researchers introduce a new method called "beholder signatures." It forces the signers to actually know the entire message before a valid signature can be created. The method also works when the message is very long, while the signature itself stays short. The researchers also provide a working proof-of-concept implementation. The method is especially useful for blockchain systems: it can prove that a storage provider has truly downloaded and stored data in full, rather than only pretending to. This strengthens the reliability of distributed storage and data-availability systems, such as those used in Ethereum. The project falls under the ATHENE research area of Cryptography.
The research paper is publicly available at  https://eprint.iacr.org/2025/1900.pdf.

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