31/08/2026
Most third party breaches reach you through a customer, a journalist or a leak site. Not the supplier.
That single fact changes how you should plan. If your process assumes a formal notification arrives first, your first few hours get spent chasing confirmation instead of containing exposure.
Two things worth building now:
Early warning signals. Watch for odd authentication patterns from supplier IP ranges, sessions that stay open long after a contractor's engagement ended, DNS changes you did not request, and your brand or domain appearing in ransomware leak site postings. These usually show up before anyone tells you anything.
A 72-hour runbook that does not depend on the supplier. Under UK rules the clock starts on your side of the contract, regardless of whose infrastructure failed. That means you need to know, in advance, what data each supplier holds, who owns the decision to notify, and how you evidence what you did.
And then the contract fixes, because the same gap tends to repeat with the next vendor.
How quickly could you list every supplier holding your personal data right now, without asking anyone?
Read the full blog: www.darkinvader.io/blog/third-party-breach-response-guide
Third party breach hitting your data? Get the early warning signals, a 72-hour UK response runbook and the contract fixes that stop a repeat.