When a startup sells software to a large organisation, the deal usually runs through a supply chain security review. In practice, a procurement team checks six things: how you manage the third-party code you depend on, whether one customer can reach another's data, how you store secrets and credentials, how you respond when something goes wrong, how you handle and store personal data, and whether an independent party has reviewed your work. The buyer expects a high standard of data protection, but they know no software is ever perfectly secure. What they are really looking for is evidence of practical safeguards that reduce their risk before they connect your product to their business.
Large buyers often assess suppliers using established frameworks, such as the UK National Cyber Security Centre's supply chain security guidance, which sets out principles for overseeing the suppliers and dependencies an organisation relies on. Here is what a procurement team actually checks when it assesses your platform.
How you manage your own supply chain
Before a buyer shares sensitive data, they want to understand the risk your product brings with it, including the third-party code it depends on. Modern applications are built on external libraries and services, and a weakness in one of those can become a weakness in yours. Procurement teams look for evidence that you know what your software depends on, keep those dependencies up to date, and have a way to react when one of them turns out to be vulnerable.
Whether one customer can reach another's data
Buyers focus heavily on data isolation, because a failure here exposes their information directly. Say your product fetches an invoice through an address such as /invoices/5001. A buyer needs to know that a logged-in user cannot simply request /invoices/5002 and see another customer's records. You satisfy this by enforcing access checks on the server for every request, confirming the user is entitled to that specific record, rather than trusting what the browser shows.
How you handle secrets and credentials
Procurement teams look closely at how you store the keys to your systems. If a developer writes an external billing token straight into the source code, anyone with access to the repository can read it. You address this by keeping application secrets in environment variables or a secrets manager rather than in the code, while storing user passwords as securely hashed values. Using parameterised database queries, rather than building them by hand, further shows disciplined engineering.
How you respond when something goes wrong
No vendor is breach-proof, and buyers know it. What they want to see is that you have thought about the bad day in advance: how you would notice a problem, who takes charge, how you contain it, and how quickly you would tell the customers affected. For a small team this does not need a heavy framework. A short written plan that names who does what, sets out how you investigate and contain an issue, and states your notification timeline is enough to show you take it seriously.
There is a hard deadline behind this question. Under UK GDPR, a personal data breach that puts people at risk must be reported to the Information Commissioner's Office within 72 hours of you becoming aware of it, and the affected individuals told without undue delay where the risk to them is high. The ICO's personal data breach guidance sets out what counts and what you must do, and a buyer will expect you to know that obligation exists.
How you handle and store personal data
Procurement teams want to understand the data itself: what you collect, why you collect it, where it lives, and how long you keep it. The principles they are checking against are straightforward. Collect only the data you actually need, encrypt it both in transit and at rest, restrict who on your team can reach it, and delete it on a clear schedule rather than keeping everything indefinitely.
Two points come up repeatedly with enterprise buyers. The first is data residency: some will require that their data stays in a particular region, such as the UK or the EU, so you should know where your database and your backups actually sit. The second is a simple data map, a short document listing what personal data you hold, where it is stored, and who can access it. It answers most of these questions in one place and signals that you manage data deliberately rather than by accident.
Whether an independent party has checked your work
Passing a procurement review takes more than a completed spreadsheet. Buyers increasingly want independent evidence that your software is actually built the way you say it is, because a team cannot reliably mark its own homework.
Our approach at Secvura is built for startups and fast-moving teams who need to understand their position quickly. We focus on a find and fix method: we carry out a thorough application security assessment to identify vulnerabilities, then give your team the guidance to put them right. That gives you independent evidence to put in front of a buyer, so your answers rest on more than a self-assessment.
Once you know what a buyer checks, the next step is answering their questionnaire well, without over-claiming. If you would like a security review of your platform first, you can get in touch through our website.