It says that the purpose of sending them the document was so that the document was analysed. You may infer (though it isn't stated) that "they" will do the analysis. This is the common sense interpretation. Sending something does not automatically cause it to be analysed so the analysis must be either done by the recipients or perhaps subcontracted by them.
By contrast something that happens automatically through the process of sending would not prompt this inference. For example, consider the example
I sent them the document (by post, not by email) to postmark it.
Here it is clear from the context that "to postmark it" is not done by "them".