The company was added to the prestigious S&P 500 Index. Also, AI.Shares of Palantir (PLTR 0.17%) rocketed 15.1% higher this week through Thursday trading, according to data from S&P Global Market Intelligence.Palantir shot up Monday on news the stock would be added to the prestigious S&P 500 index. In addition, the company announced a five-year extension with oil and gas giant BP plc, and hosted its fifth AIPCon, showing off the company's AI platform. A big achievementThe S&P 500 only admits certain compani ...