639.3—Definitions.

(a) Employer. (1) The term “employer” means any business enterprise that employs—
(i) 100 or more employees, excluding part-time employees; or
(ii) 100 or more employees, including part-time employees, who in the aggregate work at least 4,000 hours per week, exclusive of hours of overtime.

Code of Federal Regulations

Workers on temporary layoff or on leave who have a reasonable expectation of recall are counted as employees. An employee has a “reasonable expectation of recall” when he/she understands, through notification or through industry practice, that his/her employment with the employer has been temporarily interrupted and that he/she will be recalled to the same or to a similar job. The term “employer” includes non-profit organizations of the requisite size. Regular Federal, State, local and federally recognized Indian tribal governments are not covered. However, the term “employer” includes public and quasi-public entities which engage in business (i.e., take part in a commercial or industrial enterprise, supply a service or good on a mercantile basis, or provide independent management of public assets, raising revenue and making desired investments), and which are separately organized from the regular government, which have their own governing bodies and which have independent authority to manage their personnel and assets.
(2) Under existing legal rules, independent contractors and subsidiaries which are wholly or partially owned by a parent company are treated as separate employers or as a part of the parent or contracting company depending upon the degree of their independence from the parent. Some of the factors to be considered in making this determination are (i) common ownership, (ii) common directors and/or officers, (iii) de facto exercise of control, (iv) unity of personnel policies emanating from a common source, and (v) the dependency of operations.
(3) Workers, other than part-time workers, who are exempt from notice under section 4 of WARN are nonetheless counted as employees for purposes of determining coverage as an employer.
(4) An employer may have one or more sites of employment under common ownership or control. An example would be a major auto maker which has dozens of automobile plants throughout the country. Each plant would be considered a site of employment, but there is only one “employer”, the auto maker.
(b) Plant closing. The term “plant closing” means the permanent or temporary shutdown of a “single site of employment”, or one or more “facilities or operating units” within a single site of employment, if the shutdown results in an “employment loss” during any 30-day period at the single site of employment for 50 or more employees, excluding any part-time employees. An employment action that results in the effective cessation of production or the work performed by a unit, even if a few employees remain, is a shutdown. A “temporary shutdown” triggers the notice requirement only if there are a sufficient number of terminations, layoffs exceeding 6 months, or reductions in hours of work as specified under the definition of “employment loss.”
(c) Mass layoff. (1) The term “mass layoff” means a reduction in force which first, is not the result of a plant closing, and second, results in an employment loss at the single site of employment during any 30-day period for:
(i) At least 33 percent of the active employees, excluding part-time employees, and
(ii) At least 50 employees, excluding part-time employees.
Where 500 or more employees (excluding part-time employees) are affected, the 33% requirement does not apply, and notice is required if the other criteria are met. Plant closings involve employment loss which results from the shutdown of one or more distinct units within a single site or the entire site. A mass layoff involves employment loss, regardless of whether one or more units are shut down at the site.
(2) Workers, other than part-time workers, who are exempt from notice under section 4 of WARN are nonetheless counted as employees for purposes of determining coverage as a plant closing or mass layoff. For example, if an employer closes a temporary project on which 10 permanent and 40 temporary workers are employed, a covered plant closing has occurred although only 10 workers are entitled to notice.
(d) Representative. The term “representative” means an exclusive representative of employees within the meaning of section 9(a) or 8(f) of the National Labor Relations Act or section 2 of the Railway Labor Act.
(e) Affected employees. The term “affected employees” means employees who may reasonably be expected to experience an employment loss as a consequence of a proposed plant closing or mass layoff by their employer. This includes individually identifiable employees who will likely lose their jobs because of bumping rights or other factors, to the extent that such individual workers reasonably can be identified at the time notice is required to be given. The term “affected employees” includes managerial and supervisory employees, but does not include business partners. Consultant or contract employees who have a separate employment relationship with another employer and are paid by that other employer, or who are self-employed, are not “affected employees” of the business to which they are assigned. In addition, for purposes of determining whether coverage thresholds are met, either incumbent workers in jobs being eliminated or, if known 60 days in advance, the actual employees who suffer an employment loss may be counted.
(f) Employment loss. (1) The term “employment loss” means (i) an employment termination, other than a discharge for cause, voluntary departure, or retirement, (ii) a layoff exceeding 6 months, or (iii) a reduction in hours of work of individual employees of more than 50% during each month of any 6-month period.
(2) Where a termination or a layoff (see paragraphs (f)(1)(i) and (ii) of this section) is involved, an employment loss does not occur when an employee is reassigned or transferred to employer-sponsored programs, such as retraining or job search activities, as long as the reassignment does not constitute a constructive discharge or other involuntary termination.
(3) An employee is not considered to have experienced an employment loss if the closing or layoff is the result of the relocation or consolidation of part or all of the employer's business and, prior to the closing or layoff—
(i) The employer offers to transfer the employee to a different site of employment within a reasonable commuting distance with no more than a 6-month break in employment, or
(ii) The employer offers to transfer the employee to any other site of employment regardless of distance with no more than a 6-month break in employment, and the employee accepts within 30 days of the offer or of the closing or layoff, whichever is later.
(4) A “relocation or consolidation” of part or all of an employer's business, for purposes of paragraph § 639.3(h)(4), means that some definable business, whether customer orders, product lines, or operations, is transferred to a different site of employment and that transfer results in a plant closing or mass layoff.
(g) Unit of local government. The term “unit of local government” means any general purpose political subdivision of a State, which has the power to levy taxes and spend funds and which also has general corporate and police powers. When a covered employment site is located in more than one unit of local government, the employer must give notice to the unit to which it determines it directly paid the highest taxes for the year preceding the year for which the determination is made. All local taxes directly paid to the local government should be aggregated for this purpose.
(h) Part-time employee. The term “part-time” employee means an employee who is employed for an average of fewer than 20 hours per week or who has been employed for fewer than 6 of the 12 months preceding the date on which notice is required, including workers who work full-time. This term may include workers who would traditionally be understood as “seasonal” employees. The period to be used for calculating whether a worker has worked “an average of fewer than 20 hours per week” is the shorter of the actual time the worker has been employed or the most recent 90 days.
(i) Single site of employment. (1) A single site of employment can refer to either a single location or a group of contiguous locations. Groups of structures which form a campus or industrial park, or separate facilities across the street from one another, may be considered a single site of employment.
(2) There may be several single sites of employment within a single building, such as an office building, if separate employers conduct activities within such a building. For example, an office building housing 50 different businesses will contain 50 single sites of employment. The offices of each employer will be its single site of employment.
(3) Separate buildings or areas which are not directly connected or in immediate proximity may be considered a single site of employment if they are in reasonable geographic proximity, used for the same purpose, and share the same staff and equipment. An example is an employer who manages a number of warehouses in an area but who regularly shifts or rotates the same employees from one building to another.
(4) Non-contiguous sites in the same geographic area which do not share the same staff or operational purpose should not be considered a single site. For example, assembly plants which are located on opposite sides of a town and which are managed by a single employer are separate sites if they employ different workers.
(5) Contiguous buildings owned by the same employer which have separate management, produce different products, and have separate workforces are considered separate single sites of employment.
(6) For workers whose primary duties require travel from point to point, who are outstationed, or whose primary duties involve work outside any of the employer's regular employment sites (e.g., railroad workers, bus drivers, salespersons), the single site of employment to which they are assigned as their home base, from which their work is assigned, or to which they report will be the single site in which they are covered for WARN purposes.
(7) Foreign sites of employment are not covered under WARN. U.S. workers at such sites are counted to determine whether an employer is covered as an employer under § 639.3(a).
(8) The term “single site of employment” may also apply to truly unusual organizational situations where the above criteria do not reasonably apply. The application of this definition with the intent to evade the purpose of the Act to provide notice is not acceptable.
(j) Facility or operating unit. The term “facility” refers to a building or buildings. The term “operating unit” refers to an organizationally or operationally distinct product, operation, or specific work function within or across facilities at the single site.
(k) State dislocated worker unit. The term “State dislocated worker unit” means a unit designated or created in each State by the Governor under title III of the Job Training Partnership Act, as amended by EDWAA.
(l) State. For the purpose of WARN, the term “State” includes the 50 States, the District of Columbia, the Commonwealth of Puerto Rico, and the U.S. Virgin Islands.