INSURANCE

Unitrin Takeover Bid Gets Costlier: American General Corp. voiced disappointment with Unitrin Inc.’s decision to adopt a stockholder rights plan, whose purpose is to frustrate its $2.6-billion cash bid for the Chicago-based insurer. Unitrin’s plan would give stockholders the right to buy extra Unitrin shares for each share owned if anybody acquires 15% of the firm’s existing stock without board approval. The move effectively increases the number of Unitrin shares, making any takeover offer more costly. Unitrin rejected last month’s $2.6-billion offer by American General to buy the company.