The biggest public software companies are increasingly relying on acquisitions for growth, as they pick off weaker competitors or startup companies that have decided not to go it alone. In addition to their desire to get bigger, those doing the acquiring say they are responding to a move on the part of enterprise customers to reduce the number of vendors with which they do business.

Full story: How software's fastest growers got to where they are

Slide show: The list 1-40

Graphic: How software companies' financials compare

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