二重価格・価格履歴 景表法チェック — Merchant Guide
Quick summary: Record your offered-price history automatically, check every dual-price display against Japan's Consumer Affairs Agency 8-week rule, flag unsupported claims, and auto-draft the required joint-disclosure (併記) text. Free, no caps.
Why this app exists
In Japan, when you show a strikethrough "regular price" (通常価格) next to a sale price, the Consumer Affairs Agency's Premiums and Representations Act (景品表示法) guideline expects that regular price to be one the product was actually offered at over a recent period.
The benchmark is the 8-week rule:
- In the 8 weeks before the sale, the regular price must have been offered for a majority of the selling period
- Cumulatively at least 2 weeks
- Last offered within 2 weeks
Enforcement is real and current — a 2025 cease-and-desist order (措置命令) against Japanet Takata turned on a "regular price" with no recent selling record, and prefectural authorities have guided smaller online sellers too.
This app records your catalog's offered-price history automatically from the day you install, checks each dual-price display against the CAA guideline, flags displays your recorded history does not support, and drafts the joint-disclosure (併記) text stating when and for how long the price was actually offered.
What you get (every feature is free)
| Feature | What it does for you |
|---|---|
| Your price history, recorded from day one | Every variant's offered price is captured at install and on every change — the record-keeping the guideline expects, built up automatically for the whole catalog on every plan. |
| Checked against the CAA's 8-week rule | Offered at the regular price for a majority of the selling period in the trailing 8 weeks, cumulatively ≥2 weeks, and last offered within 2 weeks — anchored to the CAA guideline "不当な価格表示についての景品表示法上の考え方". Nothing is guessed. |
| Offered-price history only — no orders needed | The guideline's standard is that the price was "being sold" (offered) in normal sales activity; actual consumer-purchase records are not required. That is exactly why the app never touches order or customer data. |
| Honest three-way results | "Regular price supported", "not supported", or "still collecting history" — the app never fabricates a pass the observed history cannot substantiate. |
| Auto-drafted joint-disclosure (併記) | When the regular price does not meet the 8-week rule, the app drafts the disclosure of when and how long it was actually offered, from your recorded history (e.g. "通常価格（¥3,000）は2026年3月1日〜3月20日（20日間）に販売された価格です"). Never invented when there is no such period. |
| Storefront trust badge | Discounted products whose recorded history supports the regular price can show a factual "通常価格の販売履歴を確認済み" badge — only those, never an unverified one. |
| Audit-ready evidence export | Download the raw price-history CSV — one row per observed price, deterministic order, no editable columns. |
| Lightweight & private | Reads and writes only your own product data via write_products. No orders, no customer data, no AI. |
How it works (5 minutes to first check)
- Install — the app snapshots your catalog's current prices and starts recording history.
- Select the market — "日本 (景品表示法 二重価格表示)".
- Dashboard lists every dual-price display your recorded history does not yet support, with the reason and a draft joint-disclosure.
- Add the theme block (optional) — the "二重価格 表示バッジ" appears automatically on discounted products whose history supports the regular price.
- Export audit CSV — download the raw price history any time for your records.
What this app is / isn't (honest framing)
- It is a record-keeping and checking tool, not legal advice and not a promise of legal compliance. Whether a specific display is lawful depends on facts the app cannot see; you stay responsible for your pricing.
- Output is a computed fact (offered sale-period, cumulative days, recency, and condition met/short) — never a "lawful/unlawful" verdict. The overall judgment is yours.
- It checks offered-price history only. Actual purchase records / orders are not accessed (and the guideline's standard is the offered price, not purchase volume).
- History starts at install. The app cannot see prices from before it was installed, and says "still collecting history" instead of guessing.
- The 8-week / 2-week day counts follow the CAA guideline; they are not statutory bright lines, and the CAA looks at the whole picture.
FAQ
Does this make my dual-price displays legal?
No tool can promise that. The app records your price history, flags displays that history does not support under the CAA's 8-week rule, and drafts the joint-disclosure; the overall assessment remains yours.
What happens right after install?
Your catalog's current prices are snapshotted immediately and history accrues from there. Verdicts needing weeks of history honestly report "still collecting history".
Do you access my customers or orders?
No — the app requests only write_products. That is also why purchase-based tests are out of scope.
Which market is covered?
Japan (景品表示法 二重価格表示). The rule is encoded only after verifying the CAA primary source.
Where is my data stored?
Japan (Tokyo), on Oracle Cloud Infrastructure.
Need more compliance coverage?
| App | What it handles | Link |
|---|---|---|
| EPR Verpackung: LUCID Figures | German VerpackG packaging kilograms — calculate, reconcile dual-system & LUCID, audit CSV | epr.priceproof.app |
| GPSR Product Safety Info | EU General Product Safety Regulation — manufacturer, Responsible Person, safety warnings in buyer's language | gpsr.priceproof.app |
| EU Textile Fibre Labels | Regulation 1007/2011 — validated fibre composition in shopper's language | textile.priceproof.app |
| PriceProof: Price Proof | UK/AU/CA was-price substantiation — CMA, ACCC, Competition Act benchmarks | priceport.priceproof.app |
| PriceProof Landed Cost | Freight allocation per variant with audit trail & optional Shopify cost sync | 준비 중 |
| PriceProof Wishlist | Heart button + wishlist page, guest-friendly, free demand signals | wishlist.priceproof.app |
All apps are free with every feature included — no caps, no locked tiers, no billing flow.
Support
- Email: [email protected]
- Privacy Policy: https://pricejp.priceproof.app/privacy.html
- Terms: https://pricejp.priceproof.app/terms.html