ages, has the burden of proving that he performed work for which he was not properly compensated. The remedial nature of this statute and the great public policy which it embodies, however, militate against making that burden an impossible hurdle for the employee. Due regard must be given to the fact that it is the employer who has the duty under § 11 (c) of the Act to keep proper records of wages, hours and other conditions and practices of employment and who is in position to know and to produce the most probative facts concerning the nature and amount of work performed. Employees seldom keep such records themselves; even if they do, the records may be and frequently are untrustworthy. It is in this setting that a proper and fair standard must be erected for the employee to meet in carrying out his burden of proof.

When the employer has kept proper and accurate records, the employee may easily discharge his burden by securing the production of those records. But where the employer's records are inaccurate or inadequate and the employee cannot offer convincing substitutes, a more difficult problem arises. The solution, however, is not to penalize the employee by denying him any recovery on the ground that he is unable to prove the precise extent of uncompensated work. Such a result would place a premium on an employer's failure to keep proper records in conformity with his statutory duty; it would allow the employer to keep the benefits of an employee's labors without paying due compensation as contemplated by the Fair Labor Standards Act. In such a situation we hold that an employee has carried out his burden if he proves that he has in fact performed work for which he was improperly compensated and if he produces sufficient evidence to show the amount and extent of that work as a matter of just and reasonable inference. The burden then shifts to the employer to come forward with evidence of the precise amount of work performed or with evidence

to negative the reasonableness of the inference to be drawn from the employee's evidence. If the employer fails to produce such evidence, the court may then award damages to the employee, even though the result be only approximate. See Note, 43 Col. L. Rev. 355.

The employer cannot be heard to complain that the damages lack the exactness and precision of measurement that would be possible had he kept records in accordance with the requirements of § 11 (c) of the Act. And even where the lack of accurate records grows out of a bona fide mistake as to whether certain activities or non-activities constitute work, the employer, having received the benefits of such work, cannot object to the payment for the work on the most accurate basis possible under the circumstances. Nor is such a result to be condemned by the rule that precludes the recovery of uncertain and speculative damages. That rule applies only to situations where the fact of damage is itself uncertain. But here we are assuming that the employee has proved that he has performed work and has not been paid in accordance with the statute. The damage is therefore certain. The uncertainty lies only in the amount of damages arising from the statutory violation by the employer. In such a case "it would be a perversion of fundamental principles of justice to deny all relief to the injured person, and thereby relieve the wrongdoer from making any amend for his acts." Story Parchment Co. v. Paterson Co., 282 U. S. 555, 563. It is enough under these circumstances if there is a basis for a reasonable inference as to the extent of the damages. Eastman Kodak Co. v. Southern Photo Co., 273 U. S. 359, 377-379; Palmer v. Connecticut R. Co., 311 U. S. 544, 560-561; Bigelow v. RKO Radio Pictures, 327 U. S. 251, 263–266.

We therefore turn to the facts of this case to determine what the petitioning employees have proved and are entitled to in light of the foregoing considerations:

(1) On the issue as to the extent of the actual productive work performed, we are constrained to agree with the special master that it began and ended at the scheduled hours. This was purely a factual issue. The master made his findings in this respect through the weighing of conflicting evidence, the judging of the reliability of witnesses and the consideration of the general conduct of the parties to the suit. The master thereby concluded that productive work did not begin before the scheduled hours except in a few instances which were counterbalanced by occasions when work began after the scheduled hours or ended before the scheduled cessation of productive work. Our examination of the record leads us to acquiesce in these findings since they are supported by substantial evidence and are not clearly erroneous. And the court below correctly held that the District Court erred in failing to accept these findings and in creating a formula of compensation based upon a contrary view. Rule 53 (e) (2) of the Federal Rules of Civil Procedure. See Tilghman v. Proctor, 125 U. S. 136, 149-150; Davis v. Schwartz, 155 U. S. 631, 636–637.

(2) The employees did not prove that they were engaged in work from the moment when they punched in at the time clocks to the moment when they punched out. They were required to be ready for work at their benches at the scheduled starting times. They were given 14-minute periods in which to punch the time clocks, walk to the places of work and prepare for productive labors. But there was no requirement that an employee check in or be on the premises at any particular time during that 14-minute interval. As noted by the District Court, there was no evidence "that if the employee didn't get there by 14 minutes to seven he was fired and there is much testimony to prove that stragglers came in as late as one minute to seven." 60 F. Supp. at 149. Indeed, it would have been impossible for all members of a par

ticular shift to be checked in at the same time in view of the rate at which the time clocks were punched. The first person in line at the clock would be checked in at least 8 minutes before the last person. It would be manifestly unfair to credit the first person with 8 minutes more working time than credited to the last person due to the fortuitous circumstance of his position in line.

Moreover, it is generally recognized that time clocks do not necessarily record the actual time worked by employees. Where the employee is required to be on the premises or on duty at a different time, or where the payroll records or other facts indicate that work starts at an earlier or later period, the time clock records are not controlling. Only when they accurately reflect the period worked can they be used as an appropriate measurement of the hours worked. In this case, however, the evidence fails to indicate that the time clock records did so mirror the working time. They did not show the time during which the employees were compelled to be on the premises or at any prescribed place of work. They thus could not form the sole basis of determining the statutory workweek. See Interpretative Bulletin No. 13, paragraphs 2 and 3, issued by the Administrator of the Wage and Hour Division, U. S. Department of Labor; Wage and Hour Manual, Cumulative Edition, 1944-1945, p. 234.

(3) The employees did prove, however, that it was necessary for them to be on the premises for some time prior and subsequent to the scheduled working hours. The employer required them to punch in, walk to their work benches and perform preliminary duties during the 14-minute periods preceding productive work; the same activities in reverse occurred in the 14-minute periods subsequent to the completion of productive work. Since the statutory workweek includes all time during which

an employee is necessarily required to be on the employer's premises, on duty or at a prescribed workplace, the time spent in these activities must be accorded appropriate compensation.

No claim is here made, though, as to the time spent in waiting to punch the time clocks and we need not explore that aspect of the situation. See Cameron v.

Bendix Aviation Corp., 65 F. Supp. 510. But the time necessarily spent by the employees in walking to work on the employer's premises, following the punching of the time clocks, was working time within the scope of §7 (a). Ballard v. Consolidated Steel Corp., 61 F. Supp. 996; Ulle v. Diamond Alkali Co., 8 WHR 1042. Such time was under the complete control of the employer, being dependent solely upon the physical arrangements which the employer made in the factory. Those arrangements in this case compelled the employees to spend an estimated 2 to 12 minutes daily, if not more, in walking on the premises. Without such walking on the part of the employees, the productive aims of the employer could not have been achieved. The employees' convenience and necessity, moreover, bore no relation whatever to this walking time; they walked on the employer's premises only because they were compelled to do so by the necessities of the employer's business. In that respect the walking time differed vitally from the time spent in traveling from workers' homes to the factory. Dollar v. Caddo River Lumber Co., 43 F. Supp. 822; Walling v. Peavy-Wilson Lumber Co., 49 F. Supp. 846. Cf. Commissioner v. Flowers, 326 U. S. 465. It follows that the time spent in walking to work on the employer's premises, after the time clocks were punched, involved "physical or mental exertion (whether burdensome or not) controlled or required by the employer and pursued necessarily and primarily for the benefit of the employer