The offered price of $32 per share is a nearly 10 percent premium over Friday's closing price of $29.18.
Ancestry.com says it is a 41 percent premium over its closing price in early June or before reports surfaced that the company had retained a financial advisor for a possible sale.
Ancestry.com says it will remain headquartered in Provo, Utah, and it will continue to focus on investing in content, technology and expanding product offerings in areas like DNA.
CEO Tim Sullivan and Chief Financial Officer Howard Hochhauser will keep a majority of their equity stakes, and Spectrum Equity will remain an investor.
The company expects the deal to close early next year.
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