At a Premium

A security is said to be selling at a premium when its market price is above its par value.
Found on http://www.encyclo.co.uk/local/20174

at a premium

adverb of high value (usually because of scarcity) or above par value; `they were forced to buy it back at a premium`
Found on http://wordnetweb.princeton.edu/perl/webwn?s=at%20a%20premium
No exact match found