This is a petition for certiorari which seeks to set aside the decision rendered by the Court of  Industrial Relations on  June  18, 1954, dismissing the  complaint  for unfair labor practice filed by petitioners against respondents in an attempt to secure the reinstatement of the twenty-two (22) complainants as employees of respondent Ang Tibay, Inc.

On July  30, 1953, Ang Tibay, Inc. and the  National Workers Brotherhood,  a registered labor union, in representation of its  affiliate Pima, Inc.,  concluded a collective bargaining agreement which was approved by the Secretary of Labor.  This  agreement provides in part that the labor union  may  recommend to the  employer  the  dismissal  or separation from  service of  any  member, among several reasons, for any act of disloyalty to the union or to the employer, for any violation of any of the existing rules and regulations of the employer, or for  any violation of any provision of the by-laws and constitution of the union. The agreement also provides that the employer  recognizes the union as the sole agent of the employees and operators of the  factory of the employer  "with whom to deal  and discuss with matters affecting the relationship of management and labor."   The agreement is to  run for one year with a  right to enter into a new and more beneficial agreement for both parties.

A copy of this agreement was posted on the  bulletin board  located in the premises of the union at Caloocan, Rizal,  so that every  member of the union  could read it. At that time, the complainant, Ang Malayang Manggagawa ng  Ang Tibay Enterprises, was not yet registered  with the  Department of Labor but it was later registered  by Macario Pamintuan, one of its organizers, who later became its vice president.  The 22  complainants herein were formerly members  of both the Pima,  Inc. and the National Workers Brotherhood which concluded the  collective bargaining agreement with the employer.  Without first resigning from these two unions,  they joined in  organizing the complainant union.   Immediately after the latter was registered with the Department of Labor, it sent a  letter to the  employer demanding certain  concessions  in behalf of its members and suggesting that a collective bargaining agreement be entered into between  them.   The employer answered that it  could no  longer legally enter into any collective bargaining  agreement with said union as it had already concluded  one with the National Workers Brotherhood on July 30,  1953.

Because  the 22  complainants joined  the complainant union without first resigning from the respondent union in violation of the latter's constitution and  by-laws which make such an act punishable with  expulsion,  they  were expelled  from the  Pima, Inc.  effective August  1,  1953.  And after their expulsion, said union  requested the employer to discharge them  from their work in accordance with the provisions of paragraph  9 of the collective bargaining  agreement.   The  employer saw no  other  alternative than to dismiss them as requested.  Because of this expulsion,  a complaint for unfair  labor  practice was filed against the employer  and the two labor unions with which it concluded a  collective bargaining agreement at the instance of the 22 employees who were separated from the service.  After due hearing, the Court of Industrial Relations found the charge  unfounded whereupon  said employees, assisted by the new union with which they affiliated, interposed the  present petition for review.

The question to  be determined is whether the collective bargaining agreement concluded between the employer and respondent labor unions contains provisions Which can be considered derogatory to the provisions  concerning unfair labor practice embodied  in our Industrial Peace Act.

The pertinent  provisions of  the collective bargaining agreement which need to  be considered are:

"9. That the Party of the Second Part may recommend to the Party of the First Part dismissal or separation from service of any member for any of  the following causes: (1) insubordination; (2) acts of  immorality; (3)  theft or robbery; (4) disloyalty to  the PARTY OF THE FIRST  PART and to the PARTY OF THE SECOND PART; (5) violation of existing rules  and regulations of the PARTY OF THE FIRST PART; (6)  violation, of  the By-Laws and Constitution of  the PARTY OF THE SECOND PART; (7) threats and  acts of violence committed on the lives and property of any of the officers of the PARTY OF THE FIRST PART and any member of the PARTY OF THE SECOND PART. (Italics supplied.)

"10. That the PARTY OF THE FIRST PART agrees to recognize and cooperate with the Board of Directors of the PARTY  OF THE SECOND PART to analyze,  decide and determine whether or not any employee or operator who is a member of the PARTY OF THE SECOND PART, should be separated from the service for causes, likewise, the PARTY OF THE FIRST PART, agrees not to employ any new employee or operator unless he is a member of the PARTY OF  THE SECOND PART and without first submitting their application to the Board of Investigation;

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"17. That the PARTY OP THE FIRST PART recognizes only the PARTY OF THE SECOND PART as the sole agent of the employees and operators op the PARTY OF THE FIRST PART with whom to deal and discuss with matters  affecting  the relationship  of management  and  labor. (Italics supplied.)

"18. That the parties hereto further agree that this agreement shall be for a period of one year from date hereof and further  reserve the right after the termination of said period to enter into a new and more beneficial agreement for both parties."

And the pertinent provisions  of  the Industrial  Peace Act  which  is  invoked by  complainants is  section  4 (a), paragraph 4, of Republic Act 875, which we quote: "(a) It  shall  he unfair labor practice for an employer:

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"(4) To  discriminate in regard to hire or tenure of employment or any term or  condition  of employment to encourage membership in any labor organization: Provided, that  nothing in this Act or in any other Act or statute of  the Republic of the Philippines shall preclude an employer from making  an agreement with,  a  labor organization to require as a condition  of employment membership therein, if  such labor organization  is  the representative of  the employees as  provided in section twelve."

There   is nothing in the above-quoted  portion  of the collective bargaining agreement that  may be  considered violative  of the  provisions  of  law above-quoted for what is agreed upon therein can be considered as within the framework of the law.  Thus, it was stipulated that the employer  would  recognize the  unions as the sole, agent of all the employees of the former in all matters which affect the relationship  between management and labor.  This it is true may be considered  derogatory on the  part of the members  of  any other labor unions of the same employer which may discourage membership in one union as against another and as such destroy the right of  any laborer to self-organization, but while this may be true it however finds encouragement in the same law that prohibits it for the law recognizes the conclusion  of  a closed  shop agreement. Thus,  it is there provided that "nothing  in this Act  or in any other Act or statute of the  Republic of the Philippines shall preclude  an employer  from making an agreement with a labor organization to  require as a  condition of  employment membership therein, if such labor organization is the representative of the employees."  And this Court has  already held  that this kind of agreement is valid as it tends  to wield group  solidarity among the employees of an industrial establishment.

"With this finding we disagree, for it ignores the specific provisions  of  our law  which  precisely recognizes She conclusion  of a closed  shop agreement.   Thus,  in section  4, subsection (a),  paragraph  4, of Republic Act No.  875, it  is  expressly provided  'That nothing; in  this Act or in any other Act or statute of the Republic of the Philippines  shall  preclude an  employer  from  making' an agreement  with a  labor organization to require as  a condition of employment membership therein,  if such labor organization is the representative of  the  employees  *  * *."   And in a  similar ease where  the dismissed employees  raised the validity  of  an agreement of this nature, this Court  made the  following  comment:   "The closed-shop contract, it is said is the  most prized achievement of unionism.   It added membership and compulsory dues.  By holding out to loyal members a promise of employment in the  closed-shop, it wields, group solidarity."  (Handler, Notes, 48 Yale Law Journal, 1053,  1059, Francisco, Labor  Laws p. 186.)'  (Bacolod-Murcia  Milling-  Co.,  Inc.,  et al.  vs. National Employees-Workers  Security Union, 100 Phil., 516;  53 Off. Gaz., Nos. 3, 615,  619.)

" 'Closed-shop agreement is an agreement whereby an  employer binds himself to hire only members  of  the contracting union "who must  continue to  remain members in good standing  to keep  their jobs.   While there are  arguments  in  favor of,  and against the closed-shop agreement,  Congress, in the  exercise of  its policy-making power, has approved the closed-shop in section 4, subsection  (a) paragraph  4 of Republic Act No.  876."  (National Labor Union vs. Aguinaldo's Echague, Inc., 51  Off.  Gaz., No. 6,  2899,)

Nor can  it be said  that the stipulation providing  that the employer may dismiss an  employee whenever the union recommends his  separation either for disloyalty or for any violation of its  by-laws and constitution is  illegal or  constitutive  of unfair labor  practice,  for such is one of the matters on which management and labor can agree in order to bring about harmonious relations between them  and the cohesion  and integrity of their organization.  And as an act of loyalty a  union may certainly require its members not to  affiliate  to any labor  union and to consider  its infringement as  a reasonable cause for separation.  This is  what was done by the  respondent  union.   And the respondent employer did nothing but to put in force their agreement when  it separated  the 22  herein complainants upon  the recommendation of said union.  Such a stipulation is not.only necessary to maintain loyalty and preserve the integrity of  the  union  but is also  allowed  by our Magna Carta when it provided that while it is recognized that an employee shall have  the right to self-organization and join any  labor  organization,  it  at the  same time postulated  that  such right "shall  not impair the right of a labor organization to prescribe its own rules with respect to the  acquisition or  retention  of membership therein" [Section 4  (b),   paragraph  1, Republic Act 875].  This provision is  significant.  It  is an indirect  restriction on the right of an  employee to  self organization.  It is a solemn pronouncement of a policy that while an employee is  given the right to join a labor  organization, such right should only be asserted in a manner that will not spell the destruction of the same organization.  The law requires loyalty to the union on the part of its  members in order to obtain to the full  extent its  cohesion and integrity. We therefore see  nothing  improper in  the disputed provisions of the  collective bargaining agreement entered into between the parties.

"When a man joins a labor union (or almost any other democratically controlled group), necessarily a  portion  of his individual freedom is surrendered for the benefit of all members.  He accepts the will of the majority of the members in order that he may derive the advantages to be gained from the concerted action of all.  Just as the enactments of the legislature bind all of us, to the constitution and by-laws of the union (unless contrary to  good morals or public policy, or otherwise illegal),  which are  duly enacted through democratic processes, bind all of the members.  If  a member of a union  dislikes the provisions of the by-laws he may  seek to have them amended or may withdraw from the union; otherwise he must abide by  them. It  is not the function of courts to  decide  the wisdom  or propriety of  legitimate  by-laws  of a  trade union." (Dyer vs. Occidental  Life Ins.  Co., 17  A.L.R.  2d, 02g, 926.) "On joining' a  labor union the  constitution  and  by-laws become a part of the member's  contract  of  membership  under which  he agrees  to become  bound  by  the  constitution  and governing' rules of the union  so far as it is not inconsistent with controlling principles of law. The constitution and by laws of an unincorporated trade union express the terms of a contract, which define the privileges and rights  secured lo, and duties assumed by, those who  have become members.   The agreement  of a  member on joining a union to abide  by  its  laws and comply with  the  will  of the  lawfully constituted majority does not require  a member to submit to the determination of  the union  any  question  involving" his  personal rights."   (Jaeger,  Cases and Statutes on Labor Laws, pp. 118-119.)

"The power of  a voluntary association  to discipline  its members is not found in  the general  law  of the  land, but rests  upon the agreement of the members as expressed in its constitution and by-laws, to  which every member joining' the association is deemed to assent.  Membership in such association, therefore, imports consent to the discipline of the association if carried out in good faith and without malice, through the methods prescribed by the  laws of the association, and in accordance with the  principles of natural justice (Brennan vs. United Hatters (1906)  73 N.  J.  L.  729, 9, L.R.A. (N.S.) 254,  118  Am. St. Rep. 727, 65 Atl.  165, 9 Ann. Cas.  698). Hence, the procedure prescribed   by  the  constitution  and by-laws must be  followed; and where the constitution  or by-laws prescribed the penalty,  no other penalty may be imposed."  (Organised Labor and  Industrial conflicts Oakes, pp. 51-53.)

One final point raised by petitioners is that the respondent  unions  are  company  unions  or  controlled by the employer.   But this is  belied  by the  evidence as found  by the  industrial  court.   This finding,  which we  hereunder quote, is conclusive on this Court  (section 6, Republic Act 875):

"But  again, the complainants  charge the respondent  unions with being company  dominated,  controlled  and influenced  because  tiro Pima, Inc.,   and  its  members  do not  pay  dues to the  National Workers  Brotherhood; that  the  manager of  the  firm,  Frudencio Teodoro, is the adviser of the Pima, Inc.;  and that the firm allows the  use of its premises by this union,

"The  evidence of record, however, shows that the Pima, Inc., as branch of the National Workers  Brotherhood is paying its dues to the  latter (Exhibits 8,  8-A  to 8-E Union); that altho  Prudencio

Teodoro  was the  advisor to the Pima,  Inc., as a loan and credit association and not as a labor union, he resigned as  such after the enactment of the Industrial Peace Act; and that the free use of the firm's premises at proper  times is  extended to  all  the  employees indiscriminately.

"Upon the entire evidence, we find and conclude that the charges of unfair labor practice against the  respondents have not been substantiated."

Wherefore, the decision appealed from is affirmed, without pronouncement as to  costs.

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