Estimates from CareerBuilder indicate that one-half of American workers planned to shop sales from the office. But they may find that they can’t get to their favorite sites to take advantage of Cyber Monday deals.

In a study from Robert Half Technology, the Business News Daily reported, 60 percent of chief information officers said they are blocking all access to online shopping sites. Around 20 percent of those surveyed said they won’t block access to the sites, but will be monitoring activity “for excessive use.”

Reports from omScore detailing sales from Black Friday and this past weekend found that Amazon was the top earner, followed by Wal-Mart, Best Buy, Target and Apple. Amazon had over 50 percent more visitors than any other retailer. The company announced Monday that it had sold four times as many Kindles this year as it had last year, and saw strong sales for its new Kindle Fire tablet.

Estimates say that Cyber Monday is supposed to generate around $1.2 billion in sales, which is great — especially considering that the Business News Daily report also said that a study from Purdue University found that the U.S. economy lost around $1 billion in productivity last year on Cyber Monday.

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