KEYCORP <KEY> AGREES TO ACQUIRE UTAH BANK Keycorp said it has signed a definitive agreement to acquire Commercial Security Bancorp <CSEC> by exchanging Keycorp common valued at 63 dlrs for each Commercial Securities share. Keycorp said this gives the transaction an indicated value of 102 mln dlrs. Keycorp said the amount of its stock to be exchanged will be based on the daily average closing price of the shares for an unspecified period prior to the closing of the acquisition. Based on a maximum of about 2.75 Keycorp shares and a minimum of about 1.8 Keycorp to be exchanged, the agreement provides that if the average price of Keycorp common is less than 21.50 dlrs a share during the pricing period, the agreement will terminate unless a new conversion ratio can be negotiated. Keycorp said the transaction is designed to be tax free to Commercial Security shareholders. The company said it will treat the merger as a pooling of interests. It said the proposal is subject to approval by Commercial Security shareholders and various regulators. Keycorp said the merger is expected to become effective as soon as possible after December 31, 1987, the date Utah's interstate banking law becomes operational. Keycorp said Richard K. Hemingway and certain members of the Hemingway family who own about 30 pct of Commercial Security's outstanding shares have agreed to vote in favor of the transaction and not dispose of their stock. Based in Salt Lake City, Commercial Security ended 1986 with assets of 830.3 mln dlrs, net loans of 496.6 mln dlrs and deposits of 707.9 mln dlrs. It had net income of 5.1 mln dlrs or 3.16 dlrs a share on 1.6 mln average shares outstanding last year.