The farthest manmade leaning building is ‘Capital Gate´ which has an inclination of 18 degrees and is 160 m (524.93 ft) high. It was developed by the Abu Dhabi National Exhibitions Company, (ADNEC) and designed by RMJM and the external construction was completed in Abu Dhabi, United Arab Emirates, in January 2010.

Capital Gate is a 35 story building which forms the centre piece for the Abu Dhabi National Exhibition Centre’s development in Abu Dhabi. Capital Gate covers 50,000 squared metres.
If more than 50% of a construction is usuable floor space, it is eligible for “building” status (as opposed to tower). Source: Council on Tall Buildings and Urban Habitat, to whom we defer on such matters.