As a general rule, if a person wants to notify his or her employer or employee of an important and possibly adversarial matter, it should be done in writing. Notice is generally easier to prove if one has the writing to back it up. In addition, written notice may be a pre-requisite under an applicable statute or contract. However, one should never presume that simply because some form of notice was provided by word of mouth, it is ineffective. A good example of this is provided with respect to retaliation claims under the Fair Labor Standards Act of 1938 (“FLSA”).
The FLSA requires that employers pay overtime compensation to nonexempt employees. Pursuant to the statute it is also unlawful for an employer to “discharge or in any other manner discriminate against any employee because such employee has filed any complaint or instituted or caused to be instituted any proceeding under or related to” the FLSA provisions. This is the FLSA’s anti-retaliation provision.
Prior to 2011, certain courts interpreted the term “filed any complaint” to mean that verbal complaints were not protected under the anti-retaliation provision. However, in Kasten v. Saint-Gobain Performance Plastics, the United States Supreme Court held that the provision protects both oral and written complaints of a violation of the FLSA. Attempts to challenge this holding have, so far, failed. Thus, for example, on April 20, 2015, the Second Circuit Court of Appeals adhered to this same standard when it held that FLSA retaliation claims are not restricted to employees who file formal, written complaints with government agencies.
The fact that a complaint may be given verbally, however, does not mean that any oral communication regarding an FLSA violation (e.g. unpaid overtime) will do. Kasten cautioned that, to fall within the scope of the anti-retaliation provision, the complaint must be sufficiently clear and detailed for a reasonable employer to understand. As noted by the Fifth Circuit Court of Appeals, “not all abstract grumblings or vague expressions of discontent are actionable complaints.”
The take-away should be this: An oral complaint may suffice to put an employee within the protection of the FLSA anti-retaliation provisions. With that stated, the evidentiary benefit of a written complaint are still notable. In addition, regardless of whether verbal or written, any complaint must be sufficiently clear to constitute notice.
 Exempt employees exclude persons employed in bona fide executive, administrative, or professional capacities. The exemptions are narrowly construed against the employer.
 29 U.S.C. §215(a)(3).
 131 S. Ct. 1325 (2011).
 Greathouse v. JHS Security, Inc., No. 12-4521-CV, 2015 WL 1781036 (2nd Cir. April 20, 2015).
 Hagan v. Echostar Satellite, L.L.C., 529 F.3d 617, 626 (5th Cir. 2008).