{"document_id":"BLC-STUDY-0160","slug":"weak-subjectivity","title":"Proof of Stake: How I Learned to Love Weak Subjectivity","authors":"Vitalik Buterin","year":2014,"date_label":"2014","publisher":"Vitalik Buterin","paper_type":"Design paper","category":"Consensus","topics":["Consensus"],"source_url":"https://blog.ethereum.org/2014/11/25/proof-stake-learned-love-weak-subjectivity","source_label":"Ethereum blog, 2014","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 2014 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 node that has been offline longer than a known window must take a recent checkpoint from a source it already trusts. Inside the window, the protocol can defend itself.","canonical_url":"https://blockchainlab.com/whitepaper/weak-subjectivity","record_url":"https://blockchainlab.com/research/corpus/papers/weak-subjectivity","study_url":"https://blockchainlab.com/whitepaper/weak-subjectivity","last_reviewed":"2026-10-01","last_checked":"2026-10-01","relationships":[{"rel":"Canonical reading","label":"Weak Subjectivity study","href":"/whitepaper/weak-subjectivity"},{"rel":"Related paper","label":"Cardano","href":"/whitepaper/ouroboros"},{"rel":"Related paper","label":"Gasper","href":"/whitepaper/gasper"}]}