MAGNITE, INC. — Director's Dealing 2016

May 17, 2016

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: RUBICON PROJECT, INC. (RUBI)
CIK: 0001595974
Period of Report: 2016-05-15

Reporting Person: TAPPIN TODD L (CFO & COO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2016-05-15	Common Stock	F	8567	$14.31	Disposed	457794	Direct
2016-05-16	Common Stock	S	14063	$14.20	Disposed	443731	Direct
2016-05-17	Common Stock	S	2404	$14.21	Disposed	441327	Direct
2016-05-17	Common Stock	M	38460	$7.80	Acquired	479787	Direct
2016-05-17	Common Stock	S	38460	$14.15	Disposed	441327	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2016-05-17	Stock Option (right to buy)	$7.8	M	38460	Disposed	2023-02-01	Common Stock (38460.0)	Direct

Footnotes

F1: Shares withheld by the issuer to cover the reporting person's tax liability incurred upon the vesting of the reporting person's restricted shares.

F2: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan in order to cover the reporting person's tax liability incurred upon the vesting of the reporting person's restricted shares.

F3: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $13.99 to $14.33, inclusive. The reporting person undertakes to provide The Rubicon Project, Inc., any security holder of The Rubicon Project, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnotes 3, 4, and 5 to this Form 4.

F4: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $14.16 to $14.42, inclusive.

F5: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $14.11 to $14.20, inclusive.

F6: The option, representing a right to purchase a total of 593,650 shares, became exercisable with respect to 25% of the grant on January 28, 2014 and becomes exercisable with respect to the remainder in 36 equal installments each calendar month thereafter.

F7: Granted as compensation for services.

F8: Adjusted from the number reported on Column 9 of the Form 4 filed by the reporting person on April 29, 2016 due to an inadvertent error made when calculating the number of derivative securities beneficially owned by the reporting person following the transaction reported on the April 29, 2016 Form 4. The April 29, 2016 Form 4 should have stated that 149,762 derivative securities were beneficially owned by the reporting person following the reported transaction.