LOS ANGELES, Aug. 21 – A special administrator had been named today to manage slain hairstylist Jay Sebring’s estate, believed to exceed $500,000.

John Madden, executive vice president of Sebring Inc., was named administrator by Superior Judge Ben Koenig.

Sebring, 35, was murdered last Aug. 9 along with actress Sharon Tate, 26, coffee heiress Abigail Folger, also 26, photographer Voityck Frokowsky, 37, and Steven Parent, 18, of El Monte.

The bizarre slaying occurred at the Benedict Canyon estate rented by Miss Tate and her husband, movie director Roman Polanski.

The petition for special letters of administration was filed by Atty. Alvin G. Greenwald, who said Miss Folger was a 1% stockholder in Sebring’s successful business.

The petition noted Sebring, also known as Thomas J. Sebring, was survived by his parents, Mr. and Mrs Bernard J. Kummer, of Detroit; a brother, Frederic, also of Detroit, and two sisters, Geraldine Kummer, of the same address as the parents, and Mrs Margaret Ann Marion, of Las Vegas