The Family Pack gives consumers three upgrade licenses from Windows XP or Vista to Windows 7 Home Premium. When it started selling the $150 package in early October, Microsoft said it would offer the deal for a limited time, but did not set an end date.
On Friday, Amazon's page for the Family Pack told customers that the product would be "available to purchase until December 31, or while supplies last."
Amazon priced the Family Pack at $125.
If Amazon's stop date is accurate, Microsoft will have kept the Family Pack on the market for almost 13 weeks, more than twice as long as in 2009, when the company terminated sales after about six weeks.
Last year, customers got angry when Microsoft and retailers pulled the Family Pack from shelves without warning. Many were frustrated that they'd missed the offer, and some bloggers called the sudden disappearance a "dumb move" or pegged Microsoft as a Scrooge for dropping the deal before the holidays.
Microsoft has not announced an official end to Family Pack this year. As of late Friday, it was still selling the package through its e-store, which reiterated it was "a limited time offer and subject to stock on hand."
The Family Pack held the No. 8 spot on Amazon's software bestseller list, behind other programs such as Dragon NaturallySpeaking, Office 2010, TurboTax and Apple's upgrade to Mac OS X 10.6, aka Snow Leopard.
At Amazon's price, the Family Pack saves buyers $205 compared to the retailer's price of three separate Windows 7 Home Premium upgrade licenses, and $235 off Microsoft's list price for the same three licenses.
Windows 7 accounted for 19.7% of the world's usage share, according to statistics from Web measurement vendor Net Applications. That was an increase of 1.4 percentage points over October, and the third-largest one-month gain in 2010.
Microsoft did not immediately reply to a request for confirmation Saturday that Family Pack sales will end Dec. 31, as Amazon indicated.
