Complex sentence: Dr Stanton Glantz of the University of California obtained a pirated copy, which he screened at a public seminar in May 1982; he also gave a copy to San Francisco TV station KRON-TV, which also aired it that month.
Split into simpler sentences: Dr Stanton Glantz of the University of California obtained a pirated copy, which he screened at a public seminar in May 1982. He also gave a copy to San Francisco TV station KRON-TV, which also aired it that month.