Reliable market data is not data with a polished chart. It is data whose important claims can be traced to sources, reviewed for relevance and updated when they change. Confidence should describe the strength of the evidence for a particular claim, not the visual completeness of a profile.

Store the claim and its provenance together

For each material fact, record the exact claim, participant, source URL, source type, date observed and reviewer. A company website is a good source for what the company currently claims to offer. It is weaker proof of service quality, capacity or market share. A regulator may be authoritative for licence status but not for current buyer demand.

Freshness depends on the field

Address and contact details can change quickly; an incorporation date usually does not. Set a review cadence by field risk rather than giving every profile one stale-or-fresh badge. A broken source link or changed service page should trigger recheck of the associated claim. Preserve the date of observation even after a new version is published.

Handle conflicts without silent averaging

Two sources may disagree because they refer to different periods, jurisdictions or product names. Record the conflict, then resolve it through a stronger source or mark the claim uncertain. Do not pick the newer page automatically; a recent marketing page can still be less authoritative than a dated filing for a legal fact.

Use a review state that means something

A practical ledger can distinguish observed, participant-stated, inferred, disputed and retired claims. Reviewers should see the source and reasoning before approving a public statement. “Verified participant” on the 1000&1 Market page means public information was checked against available sources; it explicitly does not mean financial, legal or operational due diligence.

Measure quality as an operating property

Track the share of material claims with a working source, the age of high-risk observations, unresolved conflicts and correction time. These measures are more useful than counting filled fields. They show whether a Market can remain trustworthy as its underlying territory changes.

Where an evidence gap matters to a buyer decision, say what is unknown. A transparent “not confirmed” field is better than a confident sentence built from a scraped snippet.