California Public Employees Retirement System (CalPERS) disclosed Wednesday that it more than doubled its shares stakes in Gilead Sciences Inc. /zigman2/quotes/210293917/composite GILD -0.49% and Zoom Video Communications Inc. /zigman2/quotes/211319643/composite ZM +1.61% , both of which have been beneficiaries of the COVID-19 pandemic, while it rebalanced its holdings of technology-behemoths Apple Inc. /zigman2/quotes/202934861/composite AAPL -4.19% and Microsoft Corp. /zigman2/quotes/207732364/composite MSFT -3.29% by trimming its stakes during the second quarter. As of June 30, the pension fund owned 10,528,157 million shares of Gilead, which makes COVID-19 treatment candidate remdesivir, up from 4,353,093 shares as of March 31, while its Zoom Video stake increased to 341,358 shares from 61,070 shares. Among other companies with COVID-19 vaccine candidates, the stake in Moderna Inc. /zigman2/quotes/205619834/composite MRNA -2.27% increased to 599,997 shares from 449,100 shares and the Inovio Pharmaceuticals Inc. /zigman2/quotes/202993817/composite INO -5.95% holding nearly doubled to 322,441 shares from 176,365 shares. CalPERS trimmed its stakes in Apple to 9,171,757 shares from 10,190,498 shares and in Microsoft to 16,850,303 shares from 17,404,566 shares. Meanwhile, given the rallies in the stocks, the market value of CalPERS holding in Apple increased to $3.35 billion as of June 30 from $2.59 billion as of March 31, while the value of the Microsoft shares it held rose to $3.43 billion from $2.74 billion. The overall market value of CalPERS's equity holdings increased 22.7% to $101.41 billion, while the S&P 500 /zigman2/quotes/210599714/realtime SPX -2.37% gained 20.0% in the second quarter.