Facebook estimates that about 8.7 percent of all of its active accounts are fake.
According to the recently released 10-Q quarter earnings report, Facebook believes that 4.8 percent of all accounts are duplicates, user misclassified accounts were about 2.4 percent of the total and "undesirable" accounts that are used for spamming activities at 1.5 percent. The total number of accounts is currently 955 million, which puts the number of fake accounts at about 83 million.
The document also revealed that there are 552 million mobile users that log in to Facebook at least once a month. However, 5 percent of those may be based simply on the fact that mobile applications log in to Facebook without active participation of the user. Of Facebook's 955 million users, 102 million are using mobile devices only.
Meanwhile, Facebook shares have hit a new low of $19.82 during trading last week. Facebook made its stock market debut on May 18 at $38 per share.