This is a petition for certiorari filed by  Philippine Air Lines, Inc. (later referred to as the PAL) against Antonio Balanguit, et al., (Public Utilities Employees Association [FEATI Chapter] later referred to as the1 employees and the Court of Industrial Relations (CIR) to review the order of the latter dated  December 10,  1954, directing the PAL "to pay  the  money value of whatever vacation  and sick leave might have accrued  to  the employees"  listed  in the petition  of Balanguit, et al., from August 1, 1946 up  to June 15, 1947.   For the facts  of the  case, we adopt and reproduce the statement of facts made by  petitioner  in its petition which the employees in their answer admit  to be substantially correct. 

"1.  Sometime before May 21, 1947, the Philippine  Air Lines, Inc. (hereinafter referred to as PAL for  brevity)  purchased and  acquired a mijority of  the shares of the Far Eastern  Air Transport, Inc. (hereinafter referred to as FEATI, also  for brevity).   Those two airlines  were,  previous to the  said purchases, then competing  in various air routes through the Philippines, with the result that both companies were losing  and it became necessary  to maintain  only one airline.  The purchase gave rise to  the problem of what to do with the FEATI employees.  After some  negotiations between the representatives of the FEATI Employees Association and the PAL, the parties finally reached an agreement on May 21, 1947, whereby the PAL agreed to absorb some 70 per cent of  the FEATI  employees, and the said employees agreed to  work  for PAL under the same terms and conditions as they worked for the FEATI  until such time as they come to a definite understanding.  The pertinent portion  of the aforesaid  Agreement reads  as  follows:   

'1. That the  PAL will absorb all the employees and laborers that could possibly be absorbed by them belonging to the  Public  Utilities Employees Association FEATI  Chapter,  and that these employees and laborers are to work with the PAL in  accordance with the provisions of the  Collective Bargaining  Agreement entered  into between/ the previous Management of FEATI and the  representatives of the Public Utilities Employees Association  FEATI  Chapter, dated August 1, 1946, until such time as the said  Association  and the PAL Employees organization come  to a definite understanding.' 

A certified copy of the said Agreement is hereto attached and made a part hereof an Annex  "A" of this petition. 

"2.  The Collective Bargaining Agreement with the FEATI referred to in the above employment agreement of May 21, 1947 of the Public Utilities  Employees Association with the PAL was their Industrial Agreement of August 1, 1946, the pertinent portion of which granted the said  employees certain privileges, among which were:

'IV. Vacation and Sick Leave. The employees will be entitled to twelve  (12)  days  vacation leave and twelve  (12) days sick leave with pay every year, which may be cumulative.'

A certified copy of the said Industrial Agreement is hereto attached and made a part hereof  as Annex "B". 

"3.  On July 9, 1947, the PAL reached a 'definite  understanding' with  the Public  Utilities  Employees Association aforesaid whereby they  entered into an  agreement cancelling the agreements of May 21,  1947 and August  1,  1946, and declaring them 'void and  of no further force and effect.'  It  also provided for the laying off  of all the FEATI employees as  of June 15, 1947 and the payment to them of one and a half month's separation pay which amounted, roughly to P150,000.00. 

A certified copy of  said Agreement is hereto attached and made a part hereof as Annex "C". 

"4.  On November 11, 1952, almost six years from  the time they were  laid off, the  Public  Utilities  Employees Association aforesaid filed a petition with the  Court of Industrial Relations praying that the PAL be ordered  to  pay them  the  twelve  (12)  days vacation leave  and twelve (12) days  sick leave with pay, from August 1, 1946,  which had already  accrued at the time they were laid off on June  15, 1947. 

"5.  The PAL, in its Answer to  the  Employees' petition, denied liability, alleging that  it was not a party to the  Agreement of August 1,  1946.  The said employees were  absorbed by  the PAL  only on  May 21,  1947 and  were laid off on June 15, 1947. 

"6.  On December  10,  1954,  the  Court of  Industrial Relations, through  Associate Judge  V.  Jimenez Yanson,  issued  an Order requiring the PAL  to  pay the said employees the money value  of whatever vacation and sick  leave  might have accrued to the said employees from  August  1,  1946  to June 15, 1947."

According to  the PAL the amount involved, namely, the money equivalent of the vacation and sick leave which it is directed to pay by the CIR is roughly  about  P100,000.00. The  question to determine is  whether or not  the PAL is legally liable for the payment of this amount.  It is  unfortunate that the final agreement of July 9, 1946, between the PAL and FEATI on one side and the Employees on the other, failed to make any  mention whatsoever about  the money equivalent of this vacation and sick leave, whether it was payable or not and if payable, by whom.  There is no question that this leave was earned  by the employees from  the FEATI for the services rendered to it by them from August 1, 1946 (the date of the industrial agreement between them and the FEATI, when they were accorded this right to twelve  (12) days vacation leave and twelve (12) days sick leave for every year of service) up to May 21, 1947, when they ceased to  render said service to  the FEATI.  For those employees who were absorbed and continued to render service to the PAL from May 21, 1947 to  June 15, 1947 (a period  of less than one month), when they were all laid off, they may be said to have earned the corresponding leave from the PAL.   Did the PAL assume this obligation of the FEATI  to pay the equivalent of this leave which the employees earned from the FEATI?  Nothing is  said in the agreement of July 9,1947.  The employees claim  and also the CIR, though indirectly, that when  the PAL bought out the FEATI the  former assumed all  the rights and  obligations of the  latter.   This is too sweeping a statement.  In some  cases,  when one company buys  out another and continues the business of the  latter company, the buyer may be said to  assume the obligations of  the company bought out when said obligations are not of considerable amount or value,  specially when incurred in the ordinary course of trade, and  when the business of the  latter company is continued.   However, when said obligation is  of  extraordinary value,  as in  this case, amounting to about P100,000,  and the FEATI was  bought out not to continue its business but to stop its operation in order to eliminate competition,  as shown by the fact that all  the employees of the FEATI were laid-off, we cannot say that the vendee  assumed all the  obligations of the rival airline.

What the employees should have done at the time of the negotiation among the PAL, the FEATI  and themselves preparatory to the execution of  the agreement of July 9, 1947, was to raise the question as to who would pay them the equivalent of the vacation and sick leave already earned by them under the FEATI.  Had they  insisted on its payment, the FEATI could perhaps have  been made  to  pay unless, of course, the PAL agreed to assume the obligation. When they (employees)  failed to raise that  question or have it embodied in the agreement, said  failure may be regarded as a waiver of their right And when they received a  separation  pay equivalent to one  and one half months and then kept quiet about their vacation and  sick leave for a period of more than five years, there is every reason to believe that there was actually such renunciation and waiver.   It would be no surprise if this separation pay was understood  and agreed  upon by all parties to include the equivalent of leave already  earned by the  employees.  It may be  recalled that the separation pay  was not only for one month but it was for one month and a half, exceeding the "mesada" provided for in the Code of Commerce (still in force in 1947) by half a month.  It is highly possible that the extra half month  pay was to  take care of the vacation and sick leave, especially when we consider the fact that at the time of separation  on June 15, 1947, the employees had, for purposes of earning the leave, not yet  completed one year service (from August  1, 1946 to June 15, 1947).  Anyway, even assuming for a moment that the employees were  entitled to the payment  of  said leave, they were guilty of laches.  It would be unfair now to  demand this payment  from the PAL after more than five years when the papers and the records of the service of said employees from August 1, 1946 to May or June, 1947, may no longer exist; when the FEATI  has long ceased operations and  has long ceased  to exist and when its officials who were in a  position to determine which employees because of their faithful,  efficient and continuous service were entitled to leave and for how many days, may  no longer be available. 

"The purpose of vacation is to afford to a laborer a chance to get a much needed  rest to repHenish his worn out energies and acquire a new vitality to enable him to efficiently perform his duties, and not merely  to give him  additional  salary or  bounty. This privilege must be demanded in its opportune time and if he allows the years  to go  by in  silence, he waives  it.  It becomes a mere concession  or  act of grace of the employer."  (Sun-Ripe  Coconut Products, Inc. vs. National Labor Union, 97 Phil., 691; 51 O.G. 6133.)

In  view of the foregoing, the petition for certiorari is granted, and the order of the CIR of December 10, 1954, and the resolution of the CIR in bane of December 29,1954, are set aside, and the complaint of the employees  (Association)  against the PAL in Case No. 89-V(2) is  hereby dismissed, with costs.

Paras,  C. J., Bengzon, Padilla, Reyes, A., Bautista Angelo, Concepcion, Reyes, J. B. L., and Endencia, JJ., concur.