# Q02 ChatGPT — "Best face sunscreen for daily use"

**Captured 2026-09-02, logged out, 5 fresh sessions. Full-page captures.** Supersedes the
earlier provisional version built from truncated screenshots.

## Runs

| Run | Cards, in order (price · merchant) | Citations | Ad | Merchant carousel |
|---|---|---|---|---|
| 1 | EltaMD UV Clear SPF 46 $23.00·EltaMD; LRP Anthelios **UV Clear** SPF 50 $39.99·CVS; Beauty of Joseon Relief Sun $17.30·Walmart.com; CeraVe Invisible Mineral $13.99·Target; Eucerin Sun Advanced Hydration $19.99·CVS | **Prevention** +1 | **Vitality Extracts** (essential oils) | — |
| 2 | EltaMD $23.00·EltaMD; LRP Anthelios **UV Air** SPF 50 $39.99·Ulta; Beauty of Joseon **$14.26·Cult Beauty**; CeraVe $13.99·Target; Supergoop! Unseen $38.00·Target | **AAD** +1; Prevention | — | **Nordstrom** — Kiehl's ×4 ($47/$39/$33/$47) |
| 3 | EltaMD $23.00·EltaMD; LRP UV Air $39.99·Ulta; Supergoop! $38.00·Target; Beauty of Joseon $14.26·Cult Beauty; CeraVe $13.99·Target | **Prevention** +1 | **Vitality Extracts** | — |
| 4 | EltaMD $23.00·EltaMD; CeraVe $13.99·Target; Beauty of Joseon $17.30·Walmart.com; Eucerin $19.99·CVS | **Prevention** +1 | — | **Nordstrom Rack** — Shiseido Urban ×3 ($39/$39/$50), Kiehl's $62 |
| 5 | EltaMD $23.00·EltaMD; Supergoop! $38.00·Target; LRP UV Air $39.99·Ulta; Beauty of Joseon $14.26·Cult Beauty; CeraVe **$13.97·Walmart** | **Prevention and Vogue** | **IPSY** (makeup subscription) | — |

**Complete brand set:** EltaMD (5/5), CeraVe (5/5), Beauty of Joseon (5/5), La Roche-Posay
(4/5), Supergoop! (3/5), Eucerin (2/5).

## THE CENTRAL FINDING: a magazine ranking is what re-orders the shelf

**EltaMD UV Clear was the #1 pick in 5 of 5 runs. EltaMD is Google's #15.**

And ChatGPT says, unprompted, *why*:
- Run 2: "It was also ranked **the best overall face sunscreen by Prevention in 2026**."
- Run 4: "It's also currently ranked as **Prevention's best overall facial sunscreen**."
- Run 5: "It's also ranked as a top facial sunscreen by **Prevention and Vogue**."

Four of five runs cite Prevention. So:

- **The candidate pool is Google's shelf** — 100% of named brands sit in Google's top 40.
- **The ranking is not Google's** — it comes from consumer-magazine roundups.
- **"Share of text" is literally true.** Whoever wins the Prevention listicle wins the AI's top
  recommendation, over-riding fourteen products Google ranked higher.

This is the mechanism, observed rather than argued. A popularity artifact (a magazine roundup)
wearing an expertise costume (a "dermatologist-recommended" framing), selecting the single
product a shopper is told to buy.

## The decay curve, confirmed on complete data

| ChatGPT brand | Google organic position | Top 10? | Top 40? |
|---|---|---|---|
| CeraVe | 1 | ✅ | ✅ |
| La Roche-Posay | 5 | ✅ | ✅ |
| Beauty of Joseon | 8 | ✅ | ✅ |
| EltaMD | 15 | ❌ | ✅ |
| Supergoop! | 25 | ❌ | ✅ |
| Eucerin | 26 | ❌ | ✅ |

**Top 40: 6/6 = 100%. Top 10: 3/6 = 50%.** The Peec-style headline reproduces exactly at their
denominator and halves at a tighter one.

## SKU-level: 2 of 6

Exact: CeraVe Invisible Mineral SPF 50 (G#1); Supergoop! Unseen SPF 50 (G#25).
Not exact: EltaMD UV Clear **SPF 46** vs Google's SPF 50 listing; Beauty of Joseon **Relief Sun**
vs Google's **Day Dew**; LRP **UV Air / UV Clear** vs Google's **Dry Touch / UV Hydra**; Eucerin
**Sun Advanced Hydration** vs Google's **Age Defense**.

Brand 100%, SKU 33%. Identical pattern to q01.

## Price and merchant instability — cleanest example yet

**Beauty of Joseon Relief Sun SPF 50+, same product, same query, same day:**
- **$17.30 · Walmart.com** (runs 1, 4)
- **$14.26 · Cult Beauty** (runs 2, 3, 5)

**A 21% price difference across runs, with no user input changing.** No size ambiguity available
as an explanation — same named product, same SPF. This is the strongest instability example in
the dataset.

Also: **La Roche-Posay changes product identity between runs** — "Anthelios UV Clear SPF 50"
($39.99·CVS) in run 1, "Anthelios UV Air SPF 50" ($39.99·Ulta) in runs 2/3/5. Same price,
different product, different merchant.

And **EltaMD's card points to EltaMD's own store in all five runs** — the top recommendation
sends the buyer to the manufacturer, not a retailer.

## Ads: 3 of 5, all off-category

Vitality Extracts (essential oils) ×2, IPSY (makeup subscription box) ×1. **None are
sunscreen.** Running total across both queries: **5 of 10 runs (50%)**, and off-category ads
now outnumber on-category ones.

## Merchant carousels: 2 of 5, and never the recommended brands

Nordstrom pushed Kiehl's ×4; Nordstrom Rack pushed Shiseido ×3 plus Kiehl's. Neither brand was
recommended in any run. Kiehl's *is* in Google's organic top 40 (#6); Shiseido is not — it
appeared in Google's **sponsored** block.