Xlf target files contain unnecessary code

Hi all, I have translated some xlf files (originating from xml or html) and when I save the target I get some unnecessary strings which make the file useless for the client.

Source: <source>login.identity</source>

Target: <source>login.identity_small</source><seg-source><mrk mtype="seg" mid="6">login.identity_small</mrk></seg-source>

Is there a way to save the target files without these additions?

Thanks a lot,
Sandra