RALEIGH, N.C. -

North Carolina's pension system wants to be a lead plaintiff in a class-action lawsuit over Facebook's botched initial public offering.

The News & Observer of Raleigh reports Saturday that the retirement system for state workers has seen the value of its $26 million Facebook investment fall by at least $4 million.

The system last week joined a class-action lawsuit initially filed in May against the social networking site and its underwriters. Court documents filed Aug. 9 that seek lead status show the extent of North Carolina's exposure.

The state bought 685,737 shares of Facebook stock May 17 at the initial price of $38 a share. It sold a small portion the next day to make about $215,000. The state still holds about 618,000 shares. Facebook's stock closed Friday at $19.05.

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