Cupecoy's Joy, the only filly entered in Saturday's Preakness Stakes at Pimlico, was scratched at noon today by irate owner Robert Perez, who apparently was upset by the number of seats allotted to him by Pimlico.

Perez, a native of Argentina, runs a New York-based construction company and is co-owner of the filly with Robert De Fillippis. Perez attended the traditional Alibi Breakfast at Pimlico this morning, then reportedly went to the office of Pimlico General Manager Charles (Chick) Lang for his tickets for the box seats reserved for owners of Preakness entrants. He asked Lang's secretary, Nanette Blocker, for his seats.

Blocker said, "Mr. Perez came in and demanded his 30 seats. I told him that Pimlico only provides four seats and makes available another four as a practice. If he wanted more, that decision would have to be made by Mr. Lang."

According to Blocker, Perez stormed out of the office. He and trainer Alfredo Callejas, also an Argentinian, left the track shortly after 11 a.m. Before they departed, Callejas went to the racing secretary's office and formally scratched the horse.

Aquilla (Cocky) Johnson, stable manager for Pimlico, happened by the racing secretary's office and tried to pacify Perez, who was standing outside the office.

Johnson said, "I tried to tell him as best I could that we would accommodate him with 50 tickets if he would give us a chance. I offered to take him personally to Mr. Lang's office. But he was steamed up and said something about Baltimore not being nice to visitors and drove off."

Lang said, "I wish he would have given us a chance to help him. His interpretor obviously gave him the wrong information."

State Steward J. Fred Colwill, said, "Mr. Perez was within his rights to scratch his horse anytime up to 45 minutes before post time. In any other race, he would have to get the permission of the stewards."

Cupecoy's Joy, the pacesetter in the Kentucky Derby for a mile, was made a 20-to-1 choice by Pimlico oddsmaker William Merle in the overnight line. Linkage, the favorite, dropped from 7 to 5 to 6 to 5, the only change made by Merle.

Efforts to reach Perez and Callejas were unsuccessful. Groom Mario Sangroni said, "The filly goes back to New York by van tonight."