Below are insider transactions of 1,000 shares or more for publicly held companies based in Maryland or having substantial operations here. Insiders are officers, directors or owners of 10 percent or more of a corporation's stock.

Florida Rock Industries

Alvin R. Carpenter, director, purchased 1,000 shares of common stock at $28.00 each March 9 and now directly holds 3,700 shares of common.

MedImmune Inc.

Wayne T. Hockmeyer, chairman, exercised an option for 23,636 shares of common at between $3.50 and $8.25 each April 21 and now directly holds 23,636 common.

David M. Mott, director, exercised an option for 74,414 shares of common at between $5.88 and $7.00 each April 21 and now directly holds 74,414 common.

U.S. Foodservice

Lynch Kecalp LP 1991 Merrill, no longer required to file as an insider, sold 147,089 shares of common at $41.39 each March 31 and no longer holds shares in the company.

Lynch Kecalp LP 1994 Merrill, no longer required to file as an insider, sold 52,606 shares of common at $41.39 each March 31 and no longer holds shares in the company.

Pub Date: 5/10/99