SentryBay

SentryBay Limited, in London since 2007, solves a different problem than every other tool in this category: its Armored Client does not scan for malware or hunt for behavioural anomalies, it stops keylogging, screen capture and DLL injection on endpoints nobody manages — a contractor's laptop, a BYOD phone, or a VDI or DaaS session where installing a full EDR agent is not possible or not allowed.

Its own positioning is blunt about the difference: while EDR and XDR attempt to detect the threat, Armored Client is built to just stop the data loss.

That makes it a companion to the rest of this list rather than competition for ESET or Bitdefender: a company still needs anti-malware on the machines it controls, and Armored Client covers the sessions and devices it does not.

SentryBay Limited is registered in London and majority-owned by its own UK holding company, so the British jurisdiction question has a clean answer here — it sits outside the EEA under the UK's adequacy decision. Pricing and trial availability are not published; a demo has to be requested.

What SentryBay does well

• Protects unmanaged, BYOD and VDI endpoints that cannot run a full agent
• Blocks keylogging, screen capture and DLL injection specifically
• Lightweight, targeted only at chosen corporate applications
• British company, transparently and independently owned
• Works alongside existing EDR rather than replacing it

Where SentryBay falls short

• Not anti-malware; does not replace ESET, Bitdefender or the others here
• United Kingdom, outside the EEA, dependent on the adequacy decision
• No published pricing or trial

Standout feature. It protects the sessions nobody can put an agent on: SentryBay is the only tool here built for BYOD and VDI rather than managed machines.