A team led by Tamas Horvath, chairman of Yaleâs comparative medicine program, had been analyzing the pathways followed in mouse brains by ghrelin, a hormone produced by the stomach lining, when the stomach is empty.
Your IRS Electronic Filing Identification Number (EFIN) does not expire. Your IRS Preparer Tax Identification Number (PTIN) does expire every tax season. PTIN renewal occurs after October 15, and the identification number is valid through December 31 of the following year.
Tax professionals can renew their PTIN or register for a new PTIN online at www.irs.gov/ptin. Tax professionals who prefer to renew using paper can submit federal form W-12, IRS Paid Preparer Tax Identification Number Application and Renewal (downloads as a pdf); those who file using paper should be prepared to wait four to six weeks for processing.