The phrase "largest holding" usually refers to the biggest or most significant investment that an individual or organization possesses. It could be the largest amount of shares, stocks, or investments held by a person or company.
But what about not just being on the same side, but also being able to invest in the single largest holding in the common stock portfolio of his company? (dailytradealert.com)
A majority of investors may have marginal rates somewhat below these, but many with larger holdings will experience substantially higher rates. (valueinvesting.de)