Patent Sentinel Evidence Service gives both sides of an infringement question an argued, checkable answer — built from sources you can open yourself, not a confidence score you have to trust.
What it is
Patent Sentinel Evidence Service is an adversarial infringement analysis service. You give it a patent and an accused product, and it runs two arguments against each other: a prosecution brief and a defense brief, each built independently, followed by a neutral judge that weighs both and returns a verdict.
The verdict is one of three: SUPPORTED, NOT SUPPORTED, or INCONCLUSIVE, along with the controlling reason for that call. A negative or inconclusive result is treated as a normal, useful outcome — especially if you're the one defending.
Underneath the verdict is an element-by-element record: the plaintiff's position and the defendant's position on each claim element, including the defendant's strongest non-infringement or invalidity argument, stated at full strength rather than softened. Every source cited in that record can be opened and checked directly. Nothing is fabricated, and there's no inflated confidence number standing in for actual evidence.
The service runs the same way regardless of which side you're on. You bring the patent and the accused product — Kcalbin runs third-party analyses only, on the patents and products the requester brings, and the service does not expose Kcalbin's own portfolio targets to anyone.
It's built for machines first. There's a published discovery card and a live agent-to-agent task endpoint that takes a patent number, an accused product, and an accused company, with an optional list of claim numbers. The task endpoint requires a bearer API key and returns HTTP 401 without one, by design. A separate health endpoint is open, so a buyer's own agent can confirm the service is running before anyone subscribes. Keys are issued with a subscription — tell Kcalbin the volume you expect and whether you're working assertion-side or defense-side, and pricing comes back shaped to that use.
What it does not do
Similarity is never proof of claim practice. That's the operating rule the whole system runs on, not a caveat added at the end.
A verdict from this tool is not an adjudication. It reflects the openable record as it existed at the time of that run — it is screening and evidence analysis, not adjudicated infringement, and not legal advice.
It is bring-your-own-patent, bring-your-own-product: the required inputs are a patent number, an accused product, and an accused company, with claim numbers optional. Without those, there is no run.
Where that leaves you
If you need to know whether a patent position is strong enough to act on, or whether an accusation against your own product is as solid as it sounds, Patent Sentinel Evidence Service gives you a verdict plus the argument trail behind it — not a number to trust blindly, but a record built to be read, challenged, and opened element by element. The honest answer, including an inconclusive one, is treated as the point of the exercise rather than a failure of it.
Access comes through a subscription. Kcalbin asks what volume you expect and which side of the argument you'll be working from, then prices a key for that shape of use. The health endpoint is open to check before you commit to anything, and if you'd rather talk to a person first, a note to Kcalbin by email gets read — this is not an automated mailing list.