Tire Sidewall problems of the 1996 Honda Civic

Upon inspections at the tire store, all 4 of 4 pirelli p3000 cinturato (p185/65r-14) tires on my passenger car had to be replaced because of a manufacturer's defect, per the tire technician. The technician showed me a crack in the rubber running the circumference of the sidewalls, not far from the tread area. Eventually, he said the tread would separate from the rest of the tire if the tire remained in service. I have the original receipt and replacement receipts. I believe the tires were being returned to the pirelli manufacturer.