The company fell nearly 6 per cent to Dh1.44, its lowest point since 2005.
Aldar will offer 2.8 billion dirhams ($762 million) of convertible securities to Mubadala, an investment arm of the Abu Dhabi government. Mubadala will also convert a 2008 bond into equity at 11.73 dirhams a share, Aldar said in January.
It weighed on the capital's market as the Abu Dhabi Securities Exchange slipped 1.15 per cent to 2,598.16 points.
Uncertainty has clouded the regional markets and pushed institutional and foreign investors out of the markets.
In Dubai, the Dubai Financial Market lost 3.2 per cent to 1,419.14 points, the most since February 2009.
Drake & Scull International, the engineering and contracting company lost 8.5 per cent to 91 fils, the lowest point since September 2010.
Logistics courier Aramex despite the board recommending distributing a 7.5 per cent cash dividend for 2010. It fell 3.7 per cent to Dh1.53 in Dubai.
Yesterday, Saudi Arabia's Tadawul, the Arab world's largest stock exchange fell to its lowest point in 8 months after protests in Oman shook investor confidence.
There have been reports of as many as six protesters being killed in the Oman industrial city of Sohar after clashes between police and rioters.
The Egyptian stock exchange is slated to reopen for the first time in a month tomorrow after being closed in the run-up to the revolution over former president Hosni Mubarak's regime.