PrepSolution
SHRM-CPHigh-YieldEmployment Law Domain
the 40+ threshold catches people off guard

ADEA and Age Discrimination

40+

Protected Age

Only protects older workers

20+

Employees

Employer coverage threshold

1967

Year Enacted

Amended by OWBPA in 1990

What ADEA Protects

this is a one-way street

The Age Discrimination in Employment Act protects individuals who are 40 years of age or older from discrimination in hiring, promotion, discharge, compensation, and other terms and conditions of employment.

The protection is strictly one-directional. ADEA does NOT protect younger workers. A 30-year-old who is passed over in favor of a 55-year-old has no ADEA claim. A 60-year-old who is passed over in favor of a 45-year-old does have a claim, because both are 40+ and the older worker was disadvantaged.

40+

Protected Age

Only workers aged 40 and older are covered

20+

Employer Size

Only employers with 20+ employees are covered

OWBPA Waiver Requirements

heavily tested, memorize every number

The Older Workers Benefit Protection Act (1990) amended ADEA to regulate how employers can ask workers to waive their age discrimination rights. Every valid OWBPA waiver must satisfy ALL of the following requirements.

  1. 1

    The waiver must be written in plain language the employee can understand

  2. 2

    It must specifically reference ADEA rights and claims

  3. 3

    The employee cannot waive rights to future claims, only existing ones

  4. 4

    The employee must receive something of value (consideration) beyond what they are already owed

  5. 5

    The employee must be advised in writing to consult an attorney

  6. 6

    The employee gets 21 days to consider (45 days for group layoffs)

  7. 7

    The employee gets 7 days to revoke after signing

the timing is everything

21 days to consider (45 days for group layoffs), and allow 7 days to revoke. If the employer shortens either window, the entire waiver is invalid.

want to test yourself on this?

Practice questions on ADEA and age discrimination with instant feedback

Practice Now

Exam Traps

BFOQ Can Apply to Age (Narrowly)

Age can be a bona fide occupational qualification in very rare cases, like airline pilots or bus drivers where safety is directly at stake. The bar is extremely high.

Threshold Is 20, Not 15

Title VII covers employers with 15+ employees. ADEA requires 20+. If an exam question says 17 employees, ADEA does not apply.

"But-For" Causation Standard

Under Gross v. FBL Financial (2009), the plaintiff must prove age was THE reason, not just A reason. This is a higher standard than mixed-motive under Title VII.

Mandatory Retirement Is Generally Illegal

You cannot force someone to retire because of age. Limited exceptions exist for high-level executives with substantial pensions and certain public safety roles.

One-Directional

ADEA is one-directional. Only 40+.

OWBPA Waivers

OWBPA waivers need 21/45 days to consider + 7 days to revoke.

1
The Mirror

Imagine a mirror that only reflects one direction. ADEA only protects people on the 40+ side. If you are 25 and passed over for a 50-year-old, ADEA does not help you.

2
The Building Size

The mirror only exists in buildings with 20+ people. Smaller employers are not covered by ADEA at all.

3
The Waiver Envelope

If an employer asks you to sign away your ADEA rights, there are strict timing rules. You get 21 days to think (45 if it is a group layoff) and 7 days to change your mind after signing.

4
The Proof

To win, you must prove age was THE decisive factor, not merely one factor among many. This "but-for" standard is harder than the mixed-motive standard under Title VII.

Remember the number chain 40-20-21-45-7. Protected age, employer size, individual waiver days, group waiver days, revocation days.
reading is not enough, you gotta practice

Ready to test your SHRM-CP knowledge?

1,200+ practice questions written by certified professionals.

Start Practicing SHRM-CP
Reviewed by Sarah L., PrepSolution Content Editor, HR
Sources verified against SHRM 2026 standards
Updated May 2026