Sydney Harbour, at Point Piper Buoy. 13 January 2017.
Water ballast on board to allow cargo to sail on/sail off.
Vessel at 33°51'44.46" S 151°14'56.13" E

Equasis data:
IMO number : 9346029
Name of ship : YACHT EXPRESS (since 01/10/2007)
Call Sign : PCEX
MMSI : 244870311
Gross tonnage : 17951 (since 01/10/2007)
DWT : 12500
Type of ship : Heavy Load Carrier (since 01/10/2007)
Year of build : 2007
Flag : Netherlands (since 01/01/2016)

For interesting information see http://www.ship-technology.com/projects/yachtexpress/
Including

The new ship, which is the largest of its kind in the world (130ft longer than the previous biggest carrier), was built with a semi-submersible dock bay which can accept yachts of any class.

The new vessel is 209m long, 32.20m wide, 8.5m deep with a draft of 5.8m. The submerged draft is 14m, the deck length is 165m, the deck width is 31m, the deck space is 5,115m² and the weight is 15,000t (with a carrying capacity of 5,000t).