An early Amazon employee in the 1990s was given stock options worth what looked like nothing when the stock crashed 80% during the dot-com bust. The ones who held on became millionaires. A capitalization table (cap table) is simply a spreadsheet listing every owner of a company's equity — founders, employees with stock options, and every investor from seed through Series C and beyond — and exactly what percentage each one owns.
Founders usually don't own the percentage they started with by the time a company is successful — every new funding round issues new shares to new investors, and everyone else's percentage shrinks. This is dilution, and it's normal.
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