Effectivity and consistency of product data are the precondition of collaborative development pattern. Digital product model (DPM) acts as carrier of product data and relation information, and its effectivity will affect the purpose of collaborative development. The importance of DPM was emphasized and the definition of DPM was confirmed based collaborative development pattern. Two basic conceptions of configuration item, baseline and three new notions of applicability, availability and effectivity were proposed referring to Boeing and Airbus ideas. The review mechanism of configuration item and baseline was studied in detail. The method of ensure DPM-s effectivity was established by associating with the evolvement of baseline and DPM version in product development lifecycle under the configuration management. Finally, a case of definition model development was given to illustrate the validity of the method.