X0202 4 2007-04-10 0 0000075129 OTTER TAIL CORP OTTR 0001191493 KOECK GEORGE A 215 S CASCADE ST FERGUS FALLS MN 56537-2801 0 1 0 0 Corp Secretary & Gen Counsel Common Stock 2007-04-10 4 F 0 471 35.085 D 0 D Grants of Restricted Stock. On 4/10/2007, 471 shares of Common Stock were withheld by the Corporation to pay taxes due upon vesting of restricted stock, exempt pursuant to Rule 16b-3(e). No shares remain restricted. See below for other holdings: 1. Direct holding of 4,456.5839 shares of Common Stock held in the Dividend Reinvestment Program. 2. Indirect holding of 703.0591 shares of Common Stock held by ESOP. 3. 20,000 stock options with expiration date of 4/8/2011. /s/ George A Koeck by Debra J Lill -POA 2007-04-11