I've been analyzing a competitor in a competitive German automotive category. Their product has some unusual patterns, and I'm trying to figure out if they're using fake orders (brushing) without leaving reviews. Here's what I see:
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Launched about a year ago with 0 reviews, got a few sales initially (likely early reviews).
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Brief stockout, then returned to ~30 units/day, got 3 five‑star reviews, then dropped to 4 stars.
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Second stockout for 1.5 months, then back in stock and immediately doing 30+ units/day.
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Consistent 30‑40 units/day for months, rating stuck at 4.3, doesn't increase or decrease.
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No off‑site promotions found, no ads visible, no QA, no A+.
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Only ~200 reviews after a year, while competitors have thousands. Yet they stay in top 10.
I suspect they're using fake orders without reviews to boost rank and sales. How can I confirm this? Any methods to detect brushing?
Thanks.
Answers (6)
One more thing – check their seller profile and look at reviews left by buyers. If you see patterns (all 5‑star, generic text, multiple reviews from similar accounts), that's review manipulation. But brushing without reviews is harder to detect – you have to rely on sales vs. rank mismatches.
Also compare review growth rate with sales velocity. Use Keepa's estimated sales (not perfect but directional). If estimated sales are high but review count barely moves over months, that's a strong signal of brushing.
A simple rule I use: check their core keyword rank stability. Returns hurt rank. If a product stays at the top for a long time with average ratings and few reviews, it likely has very low return rates – which could be from fake orders (since fake orders don't return items).
Look at the overall category – if one seller dominates while others struggle and have similar product quality, that's a red flag. If everyone is doing similar volume, it's probably legit market demand.
A few practical checks: