The company is having RPSL-MUM-202. The largest operating unit in A.P. Moller – Maersk by revenue and staff (around 25,000 employees in 2012) is Maersk Line. In 2013 the company described itself as the world's largest overseas cargo carrier and operated over 600 vessels with 3.8 million Twenty-foot equivalent unit (TEU) container capacity. As per September 2015, being still the largest container fleet, it holds 15.1% of the global TEU. In 2006, the largest container ship in the world to that date, the E-class vessel Emma Maersk, was delivered to Maersk Line from Odense Steel Shipyard. Seven other sisterships have since been built, and on 21 February 2011, Maersk ordered 10 even larger container ships from Daewoo, the Triple E class, each with a capacity of 18,000 containers. The first were delivered in 2013. It held options for 10–20 more, and in June 2011 placed follow-on orders for a second batch of ten sisterships (to the same design) with the same shipyard, but cancelled its option for a third batch of ten. As of February 2010, Maersk had an order book for new ships totalling 857000TEU (including options on the Triple E class); that backlog is larger than the existing fleet of the fourth-largest line, Evergreen Line. Maersk Line cooperated with the US Navy on testing 7-100% algae biofuel on the Maersk Kalmar in December 2011. In January 2012 Søren Skou took over as CEO of Maersk Line from Eivind Kolding. Later that year the company ceased its business in Iran in order to prevent potential damage in the company's business with Western countries, particularly the US, due to the sanctions regime led by those countries.