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Aug 31 (Reuters) - Shares of Facebook Inc fell 4.5 percent to a new low on Friday after brokerages cut their price targets on the company's shares, saying several lock-up expirations over the next year will weigh on the stock.

Early investors got the green light to sell Facebook shares for the first time on Aug. 16, sending its stock down 6.3 percent and prompting price target cuts.

About 243 million shares will become available for trading from mid-October, with Nov. 14 being the big day when more than 1.2 billion shares will enter the market.

The company's current free float is about 628 million shares.

"We expect investor attention to return to fundamentals after the technical challenges presented by lock-up expirations over the next six months have been absorbed by the stock," BMO Capital Markets analysts said in a note.

They added that Wall Street sentiment on Facebook is now much worse than advertiser sentiment.

The brokerage cut its price target by $10 to $15, 60 percent below the price at which the company's stock started trading on May 18.

Media reports said BofA Merrill Lynch, an underwriter to the IPO, cut its price target by $12 to $23.

The company's shares fell to $18.23 on the Nasdaq on Friday amid heavy trading.

Shares of game publisher Zynga Inc, which gets most of its revenue from Facebook, slipped 3 percent on the Nasdaq. (Reporting by Sayantani Ghosh in Bangalore, Editing by Saumyadeb Chakrabarty and Sriraj Kalluvila)

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    "You will not engage in unlawful multi-level marketing, such as a pyramid scheme, on Facebook." OK, so Facebook doesn't mention of Ponzi schemes specifically, but lying, cheating and scamming are definitely out. Leave the crookery to the pros on Wall Street and stick to raising pixelated chickens on your virtual farm. Taken from Facebook's <a href="https://www.facebook.com/legal/terms" target="_hplink">Statement of Rights and Responsibilities</a>

  • Thou Shalt Not... Be A Convicted Sex Offender

    "You will not use Facebook if you are a convicted sex offender." 'Nough said. Taken from Facebook's <a href="https://www.facebook.com/legal/terms" target="_hplink">Statement of Rights and Responsibilities</a>

  • Thou Shalt Not... Play Facebook God

    "You will not provide any false personal information on Facebook, or create an account for anyone other than yourself without permission [...] You will not create more than one personal account." No Facebook profiles for dogs, no automated bots, and no accounts for 2-month-old children. Hey, wait, we kind of like this rule. Taken from Facebook's <a href="https://www.facebook.com/legal/terms" target="_hplink">Statement of Rights and Responsibilities</a>

  • Thou Shalt Not... Harass Thy Neighbor

    "You will not bully, intimidate, or harass any user." Cyberbulling has become a hot topic as social media usage continues to expand. In a recent U.K. court case, <a href="http://www.huffingtonpost.com/2012/06/08/nicola-brookes-facebook-cyberbullying_n_1580442.html" target="_hplink">Facebook was ordered to reveal the identities</a> of several bullies who had set up fake Facebook accounts to harass a 45-year-old mother. Taken from Facebook's <a href="https://www.facebook.com/legal/terms" target="_hplink">Statement of Rights and Responsibilities</a>

  • Thou Shalt Not... Be Under 13

    "You will not use Facebook if you are under 13." Not a teenager yet? Sorry, no dice. <a href="http://www.huffingtonpost.com/2011/03/23/facebook-underage-users_n_839437.html" target="_hplink">In 2011, the chief privacy adviser of Facebook said</a> that an average of 20,000 underage Facebook accounts are shut down daily. Taken from Facebook's <a href="https://www.facebook.com/legal/terms" target="_hplink">Statement of Rights and Responsibilities</a>

  • Thou Shalt Not... Spam Or Hack Facebook

    "You will not post unauthorized commercial communications (such as spam) on Facebook [...] You will not upload viruses or other malicious code." That means you, hackers and pushers of penis-enlargement pills. Taken from Facebook's <a href="https://www.facebook.com/legal/terms" target="_hplink">Statement of Rights and Responsibilities</a>

  • Thou Shalt Not... Have Free Speech

    "You will not post content that: is hate speech, threatening, or pornographic; incites violence; or contains nudity or graphic or gratuitous violence." The lines blur a little with this commandment. While the policy is meant to curb inappropriate activity, opinion is split over what makes a post unsuitable. Perhaps surprisingly, if you were to compare <a href="https://twitter.com/tos" target="_hplink">Twitter's terms of service</a> with Facebook's, you'd see that Twitter currently has no policy on hate speech. Taken from Facebook's <a href="https://www.facebook.com/legal/terms" target="_hplink">Statement of Rights and Responsibilities</a>

  • Thou Shalt Not... Post Thy Neighbor's Private Data

    "You will not post anyone's identification documents or sensitive financial information on Facebook." This one should be common sense. Taken from Facebook's <a href="https://www.facebook.com/legal/terms" target="_hplink">Statement of Rights and Responsibilities</a>

  • Thou Shalt Not... Be A Digital Salesman

    "You will not use your personal timeline for your own commercial gain (such as selling your status update to an advertiser) [...] You will not sell user data [...] You will not sell, transfer, or sublicense our code, APIs, or tools to anyone." So basically, no, you cannot profit from Facebook unless Facebook's getting a cut. Taken from Facebook's <a href="https://www.facebook.com/legal/terms" target="_hplink">Statement of Rights and Responsibilities</a>

  • Thou Shalt Not... Encourage Violation To These Rules

    "You will not facilitate or encourage any violations of this Statement or our policies." Whatever you say, Facebook. You've got the whole world in your hands. Taken from Facebook's <a href="https://www.facebook.com/legal/terms" target="_hplink">Statement of Rights and Responsibilities</a>