David F. Holstein resigned as managing director of global equities at General Motors Asset Management, effective Sept. 30, said Jerry Dubrowski, GMAM spokesman. Mr. Holstein is leaving to accept a position with Capital Group, said Mr. Dubrowski. Details on Mr. Holstein's new position could not be learned by press time; Chuck Freadhoff, spokesman for the Capital Group, could not be reached for comment. Nancy Everett, CIO of GMAM, is assuming Mr. Holstein's responsibilities while the firm searches both internally and externally for his replacement, said Mr. Dubrowski. He was unable to say if GMAM hired a recruiting firm to conduct the search.