Licence plates, credit card numbers, text messages, your page number in Game of Thrones, normal spy satellite stuff.
/s
Seriously though maybe the text wasn't in the image as much as metadata attached to it? Something like the lat/long and time of the image? I don't really know, it's a good question.
Ok these were regular land images (I think at 10m resolution) which had some text descriptions on the images. We deemed the text to be confidential enough not to outsource. Def, not spy satellite stuff :)
Are you still interested in this? I might be able to help.
I should clarify, we didn't use satellites directly, we just used the images given by a third party.