Exterior view of Yahoo! Inc., in Sunnyvale, Calif., Thursday, March 18, 2004. During the past year Yahoo! has spent more than $2 billion to acquire more search technology and established a research lab to remain on the cutting edge.(AP Photo/Paul Sakuma)

With the announcement that Yahoo! has acquired Tumblr for $1.1 billion, many have expressed skepticism for Yahoo!'s ability to manage such a purchase. Based on the company's unfortunate acquisition history, the doubter's may have a point.

Here are the 10 biggest blunder's in Yahoo! acquisition history.