Notice 2020-71, page 786.

Optional special per diem rates. This notice provides the 2020-2021 special per diem rates for taxpayers to use in substantiating the amount of ordinary and necessary business expenses incurred while traveling away from home. The notice includes (1) the special transportation industry rate, (2) the rate for the incidental expenses only deduction, and (3) the rates and list of high-cost localities for the highlow substantiation method.

REG-107911-18, page 795. This notice of proposed rulemaking supplements TD 9905 and provides rules concerning the limitation on the deduction for business interest expense. Specifically, these proposed regulations address application of the limitation in contexts involving passthrough entities, regulated investment companies (RICs), United States shareholders of controlled foreign corporations, and foreign persons with effectively connected income in the United States. These proposed regulations also provide guidance regarding the definitions of real property development, real property redevelopment, and a syndicate.