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Prior to this offering, there has been no public market for our capital stock, and we cannot assure you that a liquid trading market for our Class A common stock will develop or be sustained after this offering. Future sales of our Class A common stock in the public market, or the availability of such shares for sale in the public market, could adversely affect market prices prevailing from time to time. As described below, only a limited number of shares will be available for sale shortly after this offering due to contractual and legal restrictions on resale. Nevertheless, sales of our Class A common stock in the public market after such restrictions lapse, or the perception that those sales may occur, could adversely affect the prevailing market price at such time and our ability to raise equity capital in the future.

Based on the number of shares outstanding as of June 30, 2013, upon completion of this offering, 7,500,000 shares of Class A common stock and 53,248,648 shares of Class B common stock will be outstanding, assuming no exercise of the underwriters’ option to purchase additional shares from us, no exercise of outstanding options and the conversion of the shares sold by the selling stockholders in this offering into shares of Class A common stock. Of the outstanding shares, all of the shares sold in this offering will be freely tradable, except that any shares held by our affiliates, as that term is defined in Rule 144 under the Securities Act, may only be sold in compliance with the limitations described below.

The remaining shares of Class B common stock outstanding after this offering will be restricted as a result of securities laws or lock-up agreements as described below. Following the expiration of the lock-up period, all shares will be eligible for resale in compliance with Rule 144 or Rule 701 to the extent such shares have been released from any repurchase option that we may hold. “Restricted securities” as defined under Rule 144 were issued and sold by us in reliance on exemptions from the registration requirements of the Securities Act. These shares may be sold in the public market only if registered or pursuant to an exemption from registration, such as Rule 144 or Rule 701 under the Securities Act.

Rule 144

In general, under Rule 144 under the Securities Act, beginning 90 days after the effective date of the registration statement of which this prospectus is a part, a person (or persons whose shares are aggregated) who is not deemed to have been an affiliate of ours at any time during the three months preceding a sale, and who has beneficially owned restricted securities within the meaning of Rule 144 for at least six months (including any period of consecutive ownership of preceding non-affiliated holders) would be entitled to sell those shares, subject only to the availability of current public

information about us. A non-affiliated person who has beneficially owned restricted securities within the meaning of Rule 144 for at least one year would be entitled to sell those shares without regard to the provisions of Rule 144.

A person (or persons whose shares are aggregated) who is deemed to be an affiliate of ours and who has beneficially owned restricted securities within the meaning of Rule 144 for at least six months would be entitled to sell within any three-month period a number of shares that does not exceed the greater of one percent of the then outstanding shares of our Class A common stock (i.e. which will equal approximately 75,000 shares immediately after this offering assuming no exercise of the underwriters’ option to purchase additional shares from us, based on the number of shares of our Class A common stock outstanding as of June 30, 2013) or the average weekly trading volume of our Class A common stock reported through the NYSE during the four calendar weeks preceding such sale. Such sales are also subject to certain manner of sale provisions, notice requirements, and the availability of current public information about us.

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Rule 701

In general, under Rule 701 of the Securities Act, most of our employees, consultants or advisors who purchased shares from us in connection with a qualified compensatory stock plan or other written agreement are eligible to resell those shares 90 days after the date of this prospectus in reliance on Rule 144, but without compliance with the holding period or certain other restrictions contained in Rule 144.

Lock-Up Agreements

We, our directors and executive officers and the holders of substantially all of our common stock and securities convertible into or exchangeable for shares of our common stock, have agreed or will agree that, subject to certain exceptions and under certain conditions, for a period of 180 days after the date of this prospectus, we and they will not dispose of or hedge any shares of our common stock or any securities convertible into or exercisable or exchangeable for shares of our common stock without the prior written consent of Goldman, Sachs & Co. and J.P. Morgan Securities LLC. Goldman, Sachs & Co. and J.P. Morgan Securities LLC may, in their discretion, release any of the securities subject to these lock-up agreements at any time.

Registration Rights

Upon completion of this offering, the holders of 31,956,794 shares of our Class B common stock, including certain holders of warrants exercisable for 260,159 shares of our Class B common stock, or their transferees, will be entitled to various rights with respect to the registration of these shares under the Securities Act. Registration of these shares under the Securities Act would result in these shares becoming fully tradable without restriction under the Securities Act immediately upon the effectiveness of the registration, except for shares purchased by affiliates. See “Description of Capital Stock— Registration Rights” for additional information.

Equity Plans

Following this offering, we intend to file registration statements on Form S-8 under the Securities Act to register shares of common stock issued or reserved for issuance under our 2003 Equity

Incentive Plan, our 2010 Equity Incentive Plan, our 2013 Equity Incentive Plan and our 2013 Employee Stock Purchase Plan. This registration statement will become effective immediately upon filing, and shares covered by this registration statement will thereupon be eligible for sale in the public markets, subject to vesting restrictions, the lock-up agreements described above and Rule 144 limitations

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MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES TO NON-U.S. HOLDERS OF OUR