Returns the value of IsTypedBy attribute. This attribute represents set of relationships to the object type that provides the type definitions for this object occurrence. The then associated IfcTypeObject, or its subtypes, contains the specific information (or type, or style), that is common to all instances of IfcObject, or its subtypes, referring to the same type.

IFC4 CHANGE  New inverse relationship, the link to IfcRelDefinesByType had previously be included in the inverse relationship IfcRelDefines. Change made with upward compatibility for file-based exchange.