I am a bit confused what is your exact scenario.
You say you are exporting/importing a document to a database. If this is the case, what is the relation with pasting from external format?
Overall, pasting from external sources such as MS Word or a browser will indeed result in loss of formatting due to Silverlight's clipboard not supporting rich-text
. This should not be causing any loss of actual contents though - paragraphs, text and so on. As for your remark about the fonts - I am not sure what you mean. Was your document exported with those fonts and not imported correctly?
If you think it may help us in faster pinpointing the issue you can open a support ticket and attach the file you are trying to import, so we can investigate it. Any additional details will be appreciated.