Blockholder
The owner of a large amount of a company's shares and/or bonds, or block. In terms of shares, these owners are often able to influence the company with the voting rights awarded with their holding.
Investopedia Commentary
For example, if a mutual fund held 10 million shares in a company or 10% of the shares outstanding, they would be a blockholder and have considerable influence over who is on the board of directors.
Related Links
Knowing Your Rights As A Shareholder
What Owning A Stock Actually Means
The Purpose and Importance of Proxy Voting
See also: Block Trade, Board of Directors - B of D, Interested Shareholder, Outstanding Shares, Shareholder, Stakeholder, Voting Right
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