409A's SROF is essentially the same as Section 83's SROF.
As long as the receipt of the transferred property "is conditioned on the performance of substantial future services by any person or on the occurrence of a condition related to a purpose of the compensation," the economic benefit is subject to an SROF and is not income taxable.
In other words, Section 83 defines SROF in terms of contractual vesting.
These delayed investing techniques were essentially eliminated in 409A's SROF and, to that extent, differ from Section 83's definition.
The only other substantial difference between 83's SROF and 409A's SROF deals with controlling shareholders.
The answer lies in the observation that while all NQDC plans are subject to 409A, the code section's SROF requirement does not govern all NQDC plans
409A's SROF does not apply, therefore, to controlling shareholder deferrals in NQDC plans that are otherwise 409A-compliant.
Remember that the foundational reality facing any participant in an NQDC plan is SROF.
457, the deferred benefits must be continually subject to an SROF.
409A(d)(4) states that an employee's right to deferred compensation is subject to an SROF if the compensation is conditioned on the future performance of substantial services by any individual.
Because the employee is initiating the deferral of compensation that he or she would otherwise shortly earn and receive, it would be inappropriate to impose an SROF on the NQDCA benefits.
This is the so-called "velvet handcuff" mechanism for retaining key employees, and usually incorporates within the arrangement an SROF requiring a number of years of service before benefits become nonforfeitable.