Cookie Cloak and Dagger

Procter & Gamble is jealously proud of its Duncan Hines brand of homemade-style chocolate chip cookies. To guard the secret of its crispy-outside, chewy-inside baking technique, P & G patented it last June and then sued three rival food giants. The suits charged that the competitors have been using P & G's patented process to make "infringing cookies," and had spied at a sales presentation and at cookie plants, once even flying a plane over a facility under construction.

One of those companies, Frito-Lay, the maker of GrandMa's Rich'n Chewy, has now countersued P & G for trying to eliminate competition in the $2.4 billion-a-year packaged-cookie industry. While denying that an employee had misrepresented himself in order to filch secrets, Frito-Lay admitted that it sent a worker to photograph the outside of a Duncan Hines bakery. But, the firm said, the man's college-age son acted without its knowledge when he walked into the plant and asked for unbaked dough. Frito-Lay said it destroyed both the dough and the photos without scrutinizing either and sent P & G an apologetic note. Therefore, the company insisted, it had not been caught with its hand in the cookie jar.