About SellerEngine
SellerEngine is an EU-based operating workspace for Amazon sellers. The product and its guidance are built around the same practical question: what evidence is strong enough to support a safe decision in advertising, listings, pricing, inventory, profit or VAT?
Company identity
- Product
- SellerEngine.app
- Legal entity
- POLARSTAR OÜ
- Commercial register
- Estonia · 16838745
- VAT number
- EE102694165
- Registered address
- Tornimäe tn 5, 10145 Tallinn, Estonia
- Support
- [email protected]
Operator experience
SellerEngine was founded by Jordi Ferez Sansaloni, an Amazon seller running a multi-marketplace operation. Product workflows are designed around operational constraints: delayed attribution, marketplace-specific data, reversible changes, audit trails and the need to verify a write after a platform accepts it.
Who writes and reviews the guides
Guides are written by the SellerEngine Editorial Team and reviewed by the founder before publication. The visible byline, review date and link to this policy are part of every guide. Anonymous or unreviewed articles are not part of the governed collection.
Editorial evidence standards
Recommendations follow an explicit evidence hierarchy:
- Current official documentation, regulations and platform responses.
- Live readbacks and reconciled data from the relevant marketplace and date range.
- Transparent formulas whose inputs, units and assumptions can be inspected.
- Operational observations, clearly labelled when they are not universal rules.
We do not publish invented testimonials, unsupported performance claims or a benchmark without its sample, period and scope. A platform submission is not described as successful until the resulting state can be verified, or the remaining uncertainty is stated plainly.
Sources and methodology
Each guide links to primary material where it supports a specific claim. Calculations identify their inputs and distinguish gross, net and derived values. Marketplace, currency and date windows are kept explicit because combining incompatible scopes can create a plausible but incorrect answer. When source behavior changes, the guide is reviewed and its modified date is updated.
Original research policy
Any future SellerEngine study based on customer data must be aggregated and anonymized. It must state the sample size, marketplaces, period, inclusion rules, formula, limitations and privacy threshold. A finding that cannot pass those checks remains internal and is not presented as market-wide evidence.
Customer stories
Named customer stories identify the customer, the source used to verify its public identity and the precise scope of the SellerEngine relationship being disclosed. They do not turn an unknown result into a marketing estimate. Read how BioEssentials uses SellerEngine.app for Amazon operations, with a visible reference to the customer's official website at bioessentials.cc.
Corrections and review
Material guides are reviewed when source documentation, regulations or product behavior changes. To report an error, include the page URL and the claim that needs review in an email to [email protected]. Confirmed errors are corrected at the source and the review date is updated; they are not hidden behind a silent presentation change.
Commercial independence
Editorial placement is not sold and products are not ranked because of sponsorship. Links to SellerEngine tools are included when they implement the workflow being explained. They do not replace the evidence, assumptions or limitations required to evaluate the recommendation.