Counting rules (v0.1) Headline — public experiments matched to a standard line ID Count a public metadata record once when it has at least one match with status "accepted" and confidence >= 0.75 to a human pluripotent cell line (Cellosaurus category Embryonic stem cell or Induced pluripotent stem cell, NCBI taxonomy 9606, or an hPSCreg name attached to such a line). Grain. One record is one BioSample, GEO sample (GSM), SRA experiment (SRX/ERX, not each run), ArrayExpress SDRF sample, CELLxGENE dataset, or ENCODE accession cited by Cellosaurus. Cells are not counted. Raw reads are not stored. Deduplicate. Records that share a BioSample accession count once. A GEO series (GSE) does not count when an accepted sample from that series is already in the index. Records that cannot be linked stay separate; a GSM and a SAMN for the same biology can still both count when the crosswalk is missing. That gap is reported rather than guessed. Do not count. Flag non-human lines (any species other than human), organism conflicts, ambiguous short names (two human pluripotent lines share the alias and nothing longer breaks the tie), low-confidence hits, and non-pluripotent stem populations (mesenchymal, hematopoietic, cancer stem, and similar) are stored with a status and excluded from the headline. Skip controlled-access records (dbGaP, EGA, non-public consent) are not ingested. Distinct lines Distinct Cellosaurus accessions (CVCL_) among accepted matches. hPSCreg names are an alias of the CVCL line when Cellosaurus records the cross-reference. Linked trials ClinicalTrials.gov studies returned by the iPSC/ESC/hPSC query that the matcher links to a human pluripotent line at confidence >= 0.85, using distinctive names only (no bare H1/H9/H7). The broader hPSC trial list is reported separately and is not added to the experiment headline. Matcher 0.2 accepts a short name only for the WiCell codes H1, H7, H9, H13, and H14, and only when the cell-line field is exactly that code or the text has pluripotent context. Clone numbers, control labels, and type-word stubs (ON-iPSC reduced to "on") are not matches. A name inside a longer hyphenated code (SH-iPS15-10) is not a match. Differentiated progeny still count when the parent line is named. Matcher 0.2.1 treats a filled non-human organism name (Sus scrofa, chimpanzee, E. coli, mixed sample) as a conflict even when tax_id is blank. Matcher 0.2.2 does not accept a title that names two lines, and it does not let a title override a different line in the cell-line field. An unresolved short name in that field (bare H1, which is shared) still blocks a different line named only in the title. A name that is only stopwords plus a number (AND-3 read as "and 3") counts only when it is the whole field. Reviewed precision is an agent read of a 500-row sample, stored separately from human_label. It is not a human audit. The stats page states the sample size, the reviewed precision, and the Wilson interval from that read.