A supplier of a qualified product shall not make any changes that affect this specification without prior notification and approval by GAMESA in writing. Any change by the manufacturer may be cause for requalification. A change is defined as a change in material formulation, a significant change in the manufacturing technique which could impact the product's final properties, a change in manufacturing location, a change in raw material source which alters the manufacturer's Quality Control limits, or a change in the agreed supply criteria which may impact the product's final properties. Requalification may also be required if deemed necessary to determine that the product continues to meet all the specification requirements