ASGN Inc — Director's Dealing 2011

Dec 13, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: ON ASSIGNMENT INC (ASGN)
CIK: 0000890564
Period of Report: 2011-12-07

Reporting Person: Gibson Christina (V.P., Finance and Controller)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-12-07	Common Stock	A	5737	—	Acquired	14117	Direct
2011-12-10	Common Stock	D	141	$10.62	Disposed	13976	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2011-12-07	Non-Qualified Stock Option (right to buy)	$10.46	A	1500	Acquired	2021-12-07	Common Stock (1500)	Direct

Footnotes

F1: This award vests over a 3 year period, 25% of award vests twelve months following the grant date and the remaining 75% vests in 8 equal, consecutive quarterly installments.

F2: Executive officer elected to satisfy tax withholding obligations upon vesting by having On Assignment, Inc. withhold a number of vested shares equal to that of the employee's tax liability.

F3: Grant Vests over a four-year period: 25% on one-year anniversary and equal monthly installments thereafter .