Nvidia CEO Jensen Huang.Rick Wilking/Reuters A low-profile asset manager has been a major winner from the Big Tech stock rally this year. Jennison Associates' stakes in Tesla, Nvidia, Microsoft, Apple, and Amazon have soared in value. It held $36 billion worth of those five stocks at the end of June, up from $21 billion in December. A secretive asset manager has emerged as a massive winner from the breathless rally in Big Tech stocks this year.Jennison Associates held a combined $36 billion of Nvidia, Tesla, Microsoft, Apple, and Amazon shares at the end of June, Securities and Exchange Commission filings showed.