HEIRS OF BENIGNO SUMAGANG, REPRESENTED BY JESUS S. ABELLANOSA, MARINA BELLITA, RESURRECION CAVAN, ALEX MAPAIT AND TEODORICO SUMAGANG, PETITIONERS, VS. AZNAR ENTERPRISES, INC., AZNAR BROTHERS REALTY COMPANY, STA. LUCIA REALTY AND DEVELOPMENT INC., (CO-DEFENDANTS AND CROSS-CLAIM DEFENDANTS), HEIRS OF PERFECTA LABAYA, WITH ATTORNEY-IN-FACT IN THE PERSON OF FRANCIS R. PESTAÑO (COMPLAINANTS), TERESITA DELA CALZADA-REYES,** ET AL. (1st COMPLAINANTS-INTERVENORS), AND CELSO DEIPARINE *** (2ND COMPLAINANT-INTERVENOR), RESPONDENTS