Hijackers can attach to your Amazon listing without warning and steal your Buy Box. SentryKit monitors your ASINs 24/7 and alerts you the moment a new seller appears.
of Amazon US sales go through the Buy Box - what hijackers target first
SentryKit alert time — fix problems before most sellers even notice
Continuous monitoring — because Amazon listing issues don’t wait for business hours.
….. what SentryKit does
The short version — what it monitors, what it sends, and why it matters
SentryKit connects to your Amazon account via SP-API and continuously monitors the seller list on every tracked ASIN. When a new unauthorized seller appears, it sends you an email alert in under 30 minutes - day or night, including weekends. It also tracks Buy Box ownership changes per ASIN and maintains a timestamped log of every seller event, which sellers use as documentation when filing Brand Registry complaints with Amazon.
It monitors and alerts — giving you the early detection and evidence you need to act before revenue is lost.
….. the problem
An Amazon listing hijacker is a seller who attaches to your ASIN without authorization and competes for your Buy Box - often by undercutting your price. Amazon's open marketplace allows multiple sellers per listing, so this happens silently and instantly with no warning. In competitive categories, a hijacker can win the Buy Box within minutes. Since over 80% of purchases happen through the Buy Box, even a few hours of lost ownership means measurable revenue decline. Amazon does not send proactive notifications when new sellers attach to your listing. Sellers must manually check the Other Sellers section of each ASIN - impractical for anyone managing more than a handful of products.
US FBA private label sellers can lose thousands of dollars per month in lost Buy Box time - often without detecting the issue until monthly revenue reports reveal an unexplained drop in conversion rate.
Set up in 5 minutes. Monitor unlimited ASINs.
Get a Hijacker Alert instantly — not hours later when you finally open Seller Central.
….. how to fix it
These are the steps sellers take manually. SentryKit tells you exactly when to start - so you're never finding out hours too late.
In Seller Central, navigate to Manage Inventory and scan each ASIN for an unexpected number in the Other Sellers column. This is Amazon's only native view for surfacing unauthorized sellers - requiring you to check every product individually, with no automated refresh.
Click through to the product detail page and expand Other Sellers on Amazon. Compare names against your authorized reseller list. Document the seller's name, fulfillment type, listed price, and the exact date and time you first detected their presence.
Submit an IP infringement or counterfeit complaint through Amazon Brand Registry, or open a Seller Support case with your documentation. Acting within the first hour of detection dramatically improves your chances of removal before significant Buy Box time is lost.
….. why SentryKit
Manual monitoring is reactive - by the time you find a hijacker during a Seller Central check, they may have held your Buy Box for hours. SentryKit is proactive. Here's what that means in practice:
SentryKit monitors the seller list on every tracked ASIN continuously. The moment a new seller appears - at any hour, including weekends - you receive an email alert in under 30 minutes. Detection happens before most sellers open their laptops.
Track which seller holds the Buy Box on each ASIN in real time. When ownership shifts away from your account - to a hijacker, a repricing competitor, or due to a performance change - you get an immediate notification with the ASIN and timestamp.
Every seller event is logged with a precise timestamp: when they appeared, their price, fulfillment method, and how long they held the Buy Box. This log is exactly what Brand Registry complaints need to succeed quickly.
….. the comparison
For most FBA sellers, manual Seller Central checks are the only alternative.
Here’s what that actually looks like.
Capability
SentryKit Hijacker Alert
Manual Seller Central
Detection speed
Under 30 minutes
Hours or days — only when you check
Monitoring hours
24/7 including weekends & holidays
When you’re at your desk
Number of ASINs covered
Unlimited, automatically
One at a time, manually
Alert delivery
Instant email notification
None — you discover it yourself
Buy Box ownership data
Real-time per ASIN
Manual product page refresh
Historical seller logs
Full timestamped event history
Nothing retained automatically
Brand Registry documentation
Exportable event log
Nothing retained automatically
Works while you’re offline
Yes
No
“SentryKit caught issues I would have missed—saved me time and money instantly.“
“The alerts are spot-on and fast; I finally feel in control of my Amazon business.”
“Switching to SentryKit was the best decision—my listings are safer and my profits clearer.”
Set up in 5 minutes. Monitor unlimited ASINs.
….. all alerts
Each alert protects a different part of your Amazon business. Most sellers activate all of them on day one.
An Amazon listing hijacker is a third-party seller who attaches to your ASIN without authorization and competes for your Buy Box - often by undercutting your price. Because Amazon's marketplace allows multiple sellers per listing, any seller can attach without prior approval. Hijackers sometimes sell counterfeit products, causing negative reviews to appear on your listing even though you didn't fulfill those orders.
In competitive categories, a hijacker can win the Buy Box within minutes of attaching - particularly if they undercut your current price. Since over 80% of Amazon US sales happen through the Buy Box, even a short period of lost ownership causes immediate revenue impact. Hijackers can attach at any time, including nights and weekends.
No. Amazon does not send proactive notifications when a new seller attaches to your listing. Sellers must manually navigate to each ASIN's product detail page and check the Other Sellers on Amazon section. For sellers managing more than a few ASINs, this manual process is impractical at the frequency needed to catch hijackers before they impact revenue.
Yes. When a hijacker fulfills orders with counterfeit or substandard products, buyers leave negative reviews on your ASIN - not on the hijacker's seller profile. Because reviews attach to the listing rather than the fulfilling seller, the original brand absorbs the reputational damage even though they had no involvement in those transactions.
To remove a hijacker: first, document the unauthorized seller with screenshots; second, file an IP complaint through Amazon Brand Registry; third, open a Seller Support case if no action within 48 hours. Acting within the first hour of detection gives the best chance of removal before significant Buy Box time or revenue is lost.
SentryKit connects to your Amazon account via the Selling Partner API (SP-API) and continuously monitors the seller list associated with each tracked ASIN. When a new seller is detected, SentryKit sends an email alert in under 30 minutes. SentryKit also logs every seller event with a precise timestamp - which you can use as documentation when filing Brand Registry complaints or escalating with Seller Support.
