Complex sentence: Eventually he leaves and apparently presents a favourable report of Carter's methods and although he had claimed to want to produce a report which was as thorough as possible he indicated to Carter that certain facts would be left out to make the report more favourable to her.
Split into simpler sentences: Eventually he leaves and apparently presents a favourable report of Carter's methods. Although he had claimed to want to produce a report which was as thorough as possible, he indicated to Carter that certain facts would be left out to make the report more favourable to her.