Trust
What does a pack not tell you?
A sealed pack answers one question well: did anything change? It leaves three other questions open.
Who sealed it
Nothing in a pack proves who made it or sealed it.
Sapphire is software rooted in meaning: what’s said, from where, and how it fits together. Lines marked ‘Sapphire’ are hers.
A pack’s cover note can say where the pack came from. The seal does not check that it is true.
Source: The pack rules · sections 5 and 6
Whether a statement is true
The seal shows the cards are the ones that were sealed. It does not show that what they say is right.
A where-from tag tells you who said something, and when. Weighing it is still up to you.
Who can read it
A pack has no lock of its own. Anyone with the file can read the lines inside.
Keeping a copy private is a separate job, for the device that stores it.