{"document_id":"BLC-STUDY-0080","slug":"proofs-of-space","title":"Proofs of Space","authors":"Stefan Dziembowski, Sebastian Faust, Vladimir Kolmogorov and Krzysztof Pietrzak","year":2015,"date_label":"2015","publisher":"Stefan Dziembowski, Sebastian Faust, Vladimir Kolmogorov and Krzysztof Pietrzak","paper_type":"Design paper","category":"Consensus","topics":["Consensus"],"source_url":"https://eprint.iacr.org/2013/796","source_label":"ePrint 2013/796","legacy_pdf_path":null,"sha256":null,"sha256_note":"No hash is published. This build does not store those PDF bytes, so a checksum would be invented. Where a legacy path exists, it points at the Internet Archive copy of the old library.","version":"Source cited by the 2015 study. The study is the reading. This page does not add a second essay.","doi":null,"rights_status":"Official external source only","source_status":"Official source","use_status":"Metadata and commentary only. The reading is the study page.","licence":null,"licence_label":"No licence recorded. Rights status under review.","full_text":null,"full_text_reason":"Full text is not published on this page. Public availability is not a licence to republish a document. Blockchain Lab has not recorded a licence that permits an HTML transcription, a training set, or a retrieval corpus of the paper. Text on this page is Blockchain Lab's own wording, or a pointer to a study that is also Blockchain Lab's wording.","editorial_line":"A proof that a machine reserved storage, not that it burned energy on a puzzle. The verifier checks a small challenge. Chia is a later system that pairs this idea with a verifiable delay. The paper is not Chia.","canonical_url":"https://blockchainlab.com/whitepaper/proofs-of-space","record_url":"https://blockchainlab.com/research/corpus/papers/proofs-of-space","study_url":"https://blockchainlab.com/whitepaper/proofs-of-space","last_reviewed":"2026-10-01","last_checked":"2026-10-01","relationships":[{"rel":"Canonical reading","label":"Proofs of space study","href":"/whitepaper/proofs-of-space"},{"rel":"Related paper","label":"Verifiable delay functions","href":"/whitepaper/vdf"},{"rel":"Related paper","label":"Filecoin","href":"/whitepaper/filecoin-2017"},{"rel":"Related paper","label":"Bitcoin-NG","href":"/whitepaper/bitcoin-ng"}]}