S&P Global Headquarters, New York City. Credit: Spencer Grant/GHI/UCG/Universal Images Group via Getty Images Key Takeaways By market capitalization, Strategy is one of the largest firms in America. However, it continues to be excluded from the S&P500. Most stock indexes disqualify firms that resemble investment funds. When S&P announced quarterly index updates on Monday, Nov. 24, Strategy (formerly Microstrategy) was overlooked once again in favor of flash memory maker SanDisk, which will join th ...