First Page Sage "748% SEO ROI" — quarantined: agency's own clients, 3-year window (Q1 2021-Q3 2025), proprietary formula, no disclosed sample size, no churn accounting; their own Basic Content Marketing tier is 16%

Claim: The widely-repeated "SEO delivers 748% ROI" figure originates from First Page Sage, an SEO agency. Provenance:

• Computed on First Page Sage's own clients over a 3-year window (Q1 2021-Q3 2025).
• Uses "proprietary data" with a disclosed formula (Net Profit ÷ Campaign Cost).
• No disclosed sample size, no attribution method, no accounting for churned/failed clients — textbook survivorship + selection bias.
• The 748% number is specifically First Page Sage's premium "thought-leadership" service tier — their own Technical SEO tier is 117% and their own Basic Content Marketing tier is just 16%.
• Frequently relabelled a "median" by third-party aggregators despite being a specific service-tier number on a non-representative sample.

Adjudication: QUARANTINE. Do not quote as a typical or expected SEO ROI. Use only if explicitly framed as one agency's premium-tier internal number on their continuing clients.

Source: First Page Sage (the agency itself).

Confidence: Verified (as to provenance — the figure is well-documented). The claim that it represents typical industry ROI is not verified and is methodologically unsupportable.

Caveat: Vendor-incentivized figure — First Page Sage sells the very service the figure measures. Pair with Rule: quarantine vendor ROI multiples (748% / 22:1 / similar) — never quote as typical results.