2/24/2018 S-1 Table of Contents cancellation of any or all outstanding awards with the consent of a participant. The administrator may also buy out an award previously granted for cash, shares, or other consideration as the administrator and the participant may agree. Options. Stock options may be granted under our 2017 Plan. The exercise price per share of all options must equal at least the fair market value per share of our Class A common stock on the date of grant, unless otherwise expressly determined in writing by the administrator on the grant date. The term of an option may not exceed ten years. An incentive stock option granted to a participant who owns more than 10% of the total combined voting power of all classes of our stock on the date of grant, or any parent or subsidiary corporations, may not have a term in excess of five years and must have an exercise price of at least 110% of the fair market value per share of our common stock on the grant date. The methods of payment of the exercise price of an option include cash (by check) or shares or certain other property or other consideration acceptable to the administrator and otherwise permitted under our 2017 Plan. After a participant’s termination of service for reasons other than for death, disability, or cause, the participant generally may exercise his or her options, to the extent vested as of such date of termination, for three months after termination. After a participant’s termination of service for death or disability, the option generally will remain exercisable, to the extent vested as of such date of termination, for 12 months after such termination. In no event may an option be exercised later than the expiration of its term. After a participant’s termination of service for cause, the option generally will expire on the date of such termination. Restricted stock. Restricted stock awards may be granted under our 2017 Plan. Restricted stock awards are offers by us to sell to an eligible person shares that are subject to certain specified restrictions, including restrictions on transferability and forfeiture provisions. Restricted stock awards will be entitled to receive all dividends or other distributions paid with respect to such shares, unless the administrator provides otherwise at the time of the award. RSUs. RSUs may be granted under our 2017 Plan. RSUs are awards covering a number of shares that may be settled in cash, or by issue of those shares at a date in the future. No purchase price shall apply to an RSU settled in shares. The administrator may permit an RSU holder to defer payment under an RSU to a date or dates after the RSU is earned subject to certain restrictions set forth in our 2017 Plan. The administrator may permit holders of RSUs to receive dividend equivalent payments on outstanding RSUs if and when dividends are paid to stockholders in accordance with the terms of our 2017 Plan. Stock appreciation rights. Stock appreciation rights may be granted under our 2017 Plan. Stock appreciation rights allow the participant to receive the appreciation in the fair market value of Class A common stock between the exercise date and the date of grant. Subject to the provisions of our 2017 Plan, the administrator determines the terms of stock appreciation rights, including when such rights become exercisable and whether to pay any increased appreciation in cash or shares. The per share exercise price for the shares to be issued pursuant to the exercise of a stock appreciation right must equal at least the fair market value per share of our Class A common stock on the date of grant. The term of a stock appreciation right may not exceed 10 years from the date the stock appreciation right is signed. The administrator will determine the period of time after a participant’s termination of service during which the participant may exercise his or her stock appreciation right, subject to the same terms and conditions as applicable to options as described above. Transferability or assignability of awards. Our 2017 Plan generally does not allow for the transfer or assignment of awards, other than by will or by the laws of descent and distribution and, with respect to nonqualified options, by instrument to an inter vivos or testamentary trust in which the options are to be passed to beneficiaries upon the death of the trustor (settlor) or by gift to “family member,” and awards under our 2017 Plan may not be made subject to execution, attachment, or similar process. An award under our 2017 Plan generally is only exercisable by the participant or the participant’s legal representative during the participant’s lifetime. Certain adjustments. In the event of certain changes in our capitalization, the administrator will proportionally adjust the number of shares that may be delivered under our 2017 Plan and/or the number and 146 https://www.sec.gov/Archives/edgar/data/1467623/000119312518055809/d451946ds1.htm 154/235

Dropbox S-1 | Interactive Prospectus - Page 154 Dropbox S-1 | Interactive Prospectus Page 153 Page 155