Sign on bonus pay back clause

Q: Can anyone provide your pay back clause for offer letters that include a sign on bonus?

A: Sign-On and Retention Bonus Wording for Offer Letters sample text:
"You will also be provided with a < $ > sign-on and retention bonus at the time you commence your employment. Subject to all applicable federal and state withholding taxes, the full amount of the bonus will be advanced to you at the time you receive your first paycheck, however, it shall be actually earned on a pro-rated basis over the first year of your employment with the Company. In the event that you voluntarily resign, or are involuntarily terminated “for cause,” within twelve (12) months of the date on which your employment begins, you agree to re-pay Synteract, the unearned, pro-rated portion of this sum, pursuant to the terms stated herein. Should you have any questions regarding the tax implications of such an advance or any part of your compensation, you should consult with your own tax advisor."