Somewhat similar to IRC Section 409A, Section 457A of the Internal Revenue Code governs deferred compensation for US employees working for certain "nonqualified entities" (e.g. US citizens working for a foreign company in a tax haven such as Bermuda). While developed largely to cover offshore hedge funds, Section 457A has a broader application. In short, deferred compensation stops being tax-deferred once it vests and is no longer subject to a risk of forfeiture. Penalties like those under Section 409A can apply. For standard equity compensation settled in shares, this provision does not raise problems, though it can when RSUs have a share-deferral feature. The IRS issued guidance on this provision in Notice 2009-8 and Revenue Ruling 2014-18.