These cases relate to controversies arising out of alleged contracts of employment largely of the same general tenor between voluntary organizations which are described as labor unions and their employers, or between rival unions where one union seeks supremacy in the employment of labor in their particular field of work in the city of Haverhill.

The bill in the first case was filed on May 5, 1922. The material allegations are that on April 16, 1919, the Shoe Workers’ Protective Union entered into a written agreement, *588wherein the defendant agreed to hire only members of the union, and if such members were not available it could employ other persons until such time as union men were available, if notice was given to non-union employees that they were hired subject to such conditions. The parties in addition to this agreement entered into subsidiary agreements regulating prices and conditions of employment in certain departments of the defendant’s factory one of which dated July 19, 1920, applied to the stitching department, and is referred to as exhibit B. But as this agreement was limited in time, the parties verbally and by exhibit C agreed, that the conditions named in exhibit B should be continued in full force until a new agreement was consummated. The defendant is charged with having refused “ to carry out the terms and conditions of the old agreement ” and with having “ violated the terms of the verbal and written agreement,” by refusing to pay the price named in exhibit B for new work. It also is alleged that the employees are not permitted to have a shop committee; that the business agent is not allowed to visit the factory during working hours, while prices for defective new work have been fixed by the defendant without consultation with the Shoe Workers’ Protective Union, or the Stitchers’ Union whose members “ are put to work without a permit from the Union and “ work having no piece price is not paid for by the hour ” at the rate stipulated under the head of “ remarks ” in exhibit B, but “ the price paid is less than the piece price.” The prayers for relief are that the defendant may be enjoined from violating the terms of the verbal and written agreements and for an accounting and the assessment of damages. It was agreed at the hearing before the master that exhibit A was terminated April 15, 1922, and the bill states that exhibit B “ expired by its own limitation ” July 18, 1921. But it is contended that the conditions of employment shown under the head of remarks in exhibit B were to continue in effect until “ the signing of a new list ” as provided in exhibit C. It is found however that no written agreement was ever entered into after the expiration of exhibit B. The plaintiff also claimed that an oral agreement *589extending the conditions for a period identical with the period named in exhibit C was expressly made, or resulted by implication from the subsequent industrial relations of the union and the defendant, and that there was as matter of fact an observance of these conditions subsequent to July 18, 1921. But on unreported evidence the master finds that this was done as a matter of practice and not as matter of agreement, and no implied contract has been established. The parol evidence rule also applies, and exhibit C stood as explaining the working arrangements between the union and the defendant after exhibit B terminated. DeFriest v. Bradley, 192 Mass. 346. Mears v. Smith, 199 Mass. 319, 322. The defendant on January 7, 1922, closed its factory in Haverhill because of local labor difficulties, and moved to Lowell, where independently of the agreement shown by exhibits B and C read in combination, it employed nonunion labor and conducted its factory as an “ open shop.” The plaintiff, whose membership and general agency terminated May 1,1922, and who never was a stitcher or employed by the defendant, brought on January 27, 1922, a bill in equity in behalf of the union and its members, the allegations of which and the relief asked for are not in the record. By an interlocutory decree the defendant was enjoined “ until and including April 15, 1922, from hiring or employing any shoe operatives ... in Lowell who are not members of the . . . union where members of said union are available to work in said factory unless said union assents in writing to such hiring.” The defendant in obedience to the injunction closed its factory, and requested the plaintiff to furnish at once sufficient members of the union to operate the stitching room. But a sufficient number were not provided, and the plaintiff, after admitting that stitchers could not be supplied, finally assented in writing to the employment of non-union members and agreed to issue irrevocable permits to those employed “ where union members are not available.” The defendant thereafter was compelled to employ stitchers who were not members of the union to operate its factory, and refused permission to the agent of the stitchers’ local union to visit the stitching room, because, *590as the master reports, the defendant took the position that the agent of the stitchers’ union had no authority under the circumstances to make an inspection. The defendant on April 17, 1922, moved its “ cutting room ” to Haverhill where the operation of cutting has since been performed by its own operatives employed without recognition of the demands of the union. If exhibit C is held to have continued exhibit B in force, the employment of non-union stitchers, the refusal of inspection by the agent of the stitchers union, the denial of a shop committee, and the payment of lower wages to those stitchers than the wages specified in exhibit B are assigned as breaches of the agreement. But the claim for damages has been waived, and, quite aside from the position taken by the defendant, that the suit cannot be maintained by the plaintiff in his own name even if it was begun for “ and on behalf of the Shoe Workers’ Protective Union and its members ” and by their authority, Donovan v. Danielson, 244 Mass. 432, it is plain on the foregoing review, that the remedy by injunctive relief would be the issuance of a mandatory injunction compelling the defendant to employ only stitchers of the union, which the master finds the union admitted could not be furnished. It should not be granted. Hapgood v. Shaw, 105 Mass. 276, 279. See Rice v. D’Arville, 162 Mass. 559; Garcin v. Pennsylvania Furnace Co. 186 Mass. 405, 411; Butterick Publishing Co. v. Fisher, 203 Mass. 122, 130. The question, whether in any event specific performance would be decreed of a contract solely for the performance of personal services of the nature and under the conditions of the contract in question, need not be decided.

The members of the Boot and Shoe Workers’ Union bring suit in the second case against the Shoe Workers’ Protective Union and a copartnership who are manufacturers of shoes, doing business under the firm name of Triangle Shoe Company, to which we shall refer as the company. The demurrants admit, that the object and purpose of the defendants are to induce all shoe workers of Haverhill to join their association in preference to the union of the plaintiffs, and to induce all the shoe manufacturers, “ and proprietors of *591allied industries in . . . [the city], to agree upon the terms of employment, compensation of employees, and working hoars ” and other conditions, as established by their union. In furtherance of this general policy the defendants “ have unlawfully conspired to drive the Boot and Shoe Workers’ Union out of the city of Haverhill, and by solicitation, intimidation, threats, violence and show of force, to cause manufacturers under contract with the . . . Boot and Shoe Workers’ Union to repudiate such contracts,” and to cause members of the union of the plaintiff “ to repudiate their individual contracts of employment with ■ such manufacturers.” But the active efforts of the defendants are alleged to have been more direct and specific. The plaintiffs and the company on April 21, 1921, entered into a contract whereby the defendants agreed to furnish to the company its union stamp free of charge, and to make no additional price for the use of the stamp, to make no discrimination between the company and other firms, persons or corporations who may enter into an agreement with the union for the use of the union stamp, and to make all reasonable effort to advertise the union stamp, and to create a demand for the union stamped products of the company, in common with other employers using the union stamp. The other material conditions of the contract relating to terms of employment are substantially similar to the contract referred to in the first case. The allegations of the bill are explicit, and the defendants again admit that while this contract was in force and with knowledge of it and while members of the plaintiffs unior were working for the company under it, they induced or coerced the company by threats and intimidation to join “ the conspiracy ” to ruin the union of the plaintiffs, and that the company acting in combination with the members of the defendants’ union have notified the plaintiffs, who are ready ar>d willing to perform, of their intention to repudiate the contract which was in full force when the bill was filed. The case stated ordinarily would be governed by Walker v. Cronin, 107 Mass. 555, and kindred decisions, and the bill could be maintained. But the defendants, contend on various grounds *592that the contract is illegal and they are immune from all , liability. We are of opinion that none of the alleged causes of demurrer are well taken. The remedy at law is not plain and adequate, and the plaintiffs are not shown to have participated in the wrongful conduct of the defendants at any stage of the controversy. The bill is not multifarious, nor are the allegations so vague and indefinite that the defendants are not sufficiently informed of the nature of the complaint to enable them to make their defence, nor is there any question of mutuality of obligation, or remedy; for specific performance is not asked. The defendants in what they did were not acting under an alleged right to strike for the protection of their industrial or economic interests, but were endeavoring to destroy the individual rights of fellow workmen unless they submitted to their dictation and control. ■ The story is directly and clearly told by the-bill which as to parties is properly brought, and the defendants, being strangers to the contract and claiming no benefits under it, cannot attack its execution by the plaintiffs’ general president, or its validity as between the parties. Green v. Kemp, 13 Mass. 515. Borden v. Boardman, 157 Mass. 410, and cases cited. Shinsky v. Tracey, 226 Mass. 21. Tracey v. Osborne, 226 Mass. 25, 29. Raynes v. Sharp, 238 Mass. 20. Donovan v. Danielson, 244 Mass. 432. Rice v. Manley, 66 N. Y. 82. Ellsworth v. Mitchell, 31 Maine, 247. It is further contended that the contract creates a monopoly, is against public policy, is in restraint of trade, is unconscionable, and is in contravention of G. L. c.. 93, § 2, and she “ Federal Anti-Trust Law,” 26 U. S. Sts. at Large, 209, c. 647. The bill however asks to have the defendants enjoined “ from intentionally doing anything, without legal justification, to his injury.” Davis v. New England Railway Publishing Co. 203 Mass. 470, 478. Whatever may be shown at a trial on the merits, it cannot be said on the present record as matter of law that a federal question is involved or the contract is in restraint of trade, either at common law or under the statute. See Hopkins v. United States, 171 U. S. 578, 592. G. L. c. 93, § 2. The union stamp is not a trading stamp, the control of which under certain conditions may result in a monopoly, as pointed *593out in Merchants Legal Stamp Co. v. Murphy, 220 Mass. 281. It is a label or trademark showing that products bearing the stamp are made by the manual labor of members of the plaintiffs' union. Its use cannot be said on the averments of the bill to be designed to suppress competition or generally to control the manufacture of shoes put upon the market, or to prejudice the public by restriction of production, or by enhancement of prices. Quincy Oil Co. v. Sylvester, 238 Mass. 95. Taylor v. Blanchard, 13 Allen, 370. Commonwealth v. Strauss, 191 Mass. 545, and similar cases are not in conflict. It may be that there are provision's which a court of equity in its discretion would not enforce by specific performance. But the denial of such relief would not render the entire contract illegal or voidable. Hoban v. Dempsey, 217 Mass. 166. The contract, in so far as it related to the exclusive employment of union labor, cannot, in the absence of further allegations or of evidence, be condemned as illegal because tending to foster a monopoly, or to violate the anti-trust law. Smith v. Bowen, 232 Mass. 106, 110. Shinsky v. O’Neil, 232 Mass. 99, 102. Ryan v. Hayes, 243 Mass. 168. Berry v. Donovan, 188 Mass. 353, is distinguishable for reasons stated in Hoban v. Dempsey, supra. See also Minasian v. Osborne, 210 Mass. 250, 255; Shinsky v. O’Neil, supra; Folsom Engraving Co. v. McNeil, 235 Mass. 269, 278. It is not rendered invalid because of the clause relating to the arbitration of differences which may arise between the employer and employee, for reasons stated in Marsch v. Southern New England Railroad, 230 Mass. 483, 493, 494. Nor is the contract itself as matter of law done away with by these attacks, although at a trial on the merits the evidence may show that under all the circumstances it was entered into for the sole purpose of unjustifiably stifling competition and preventing the free flow of labor, Haverhill Strand Theatre, Inc. v. Gillen, 229 Mass. 413, 418, and that the members of the union who left the employment of the company are included among the parties plaintiff. The contract however was for the benefit of all the members, and if they are not included, or if as to them the suit is discontinued, the other members should not be deprived of *594their individual rights against .the defendants who will not be permitted to take advantage of their own wrongdoing in procuring the abandonment of their work by the company’s employees for the purpose of accomplishing an abrogation of the contract, as stated in the bill.

The plaintiff corporation in the third case is a manufacturer of shoes at its factory in Haverhill where for some years prior to filing the bill it had carried on business, and the labor unions previously named were located. The presiding judge has found, that, although defectively executed by the Boot and Shoe Workers’ Union, yet by ratification of the parties the plaintiff and the union on June 2, 1917, entered into a contract, permitting the plaintiff to use the union stamp on condition that the corporation should employ only members of the union in good standing. The defendants earnestly contend that this finding is erroneous. But the evidence is not reported. It must be presumed that all the elements required to show ratification were sufficiently proved, and the general finding accordingly must stand. Remick v. Sandford, 118 Mass. 102. New England Dredging Co. v. Rockport Granite Co. 149 Mass. 381. W. A. Snow Iron Works, Inc. v. Chadwick, 227 Mass. 382, 390, 391. The terms of the contract, which do not materially differ as to conditions of employment from those already discussed, were observed by the parties for more, than five years, and on October 4, 1922, as the judge states, the plaintiff had in its employment one hundred and eighty members of the Boot and Shoe Workers’ Union and about thirty members of the Shoe Workers’ Protective Union. It appears that these unions were rival organizations each striving to increase its membership at the expense of the other, and at a meeting of the Shoe Workers’ Protective Union it was voted, “that those who wished to belong to the Shoe Workers’ Protective Union only should finish the work they had on hand in the factories in which they were employed . . . quit work and report at the . . . headquarters ” of the union. The reason for this action is stated to have been, that the Boot and Shoe Workers’ Union not being able to supply sufficient members under their contracts, resorted to the *595membership of the Shoe Workers’ Protective Union for reinforcements. But members so obtained were employed merely to enable the Boot and Shoe Workers’ Union to perform its contracts and they were not allowed to hold office or to be delegates under the constitution of the employing union. The defendants pursuant to the vote sent on October 4, 1922, fifteen members who were not employees of the plaintiff to picket its factory where there was no strike, nor any dispute between the plaintiff and its employees “ unless the desire of the Shoe Workers’ Protective Union to get all the work in the plaintiff’s factory for themselves may be called a trade dispute.” The blow fell without warning for “ they had not complained to the plaintiff in reference to labor conditions in the factory.” It was undisputed that the defendants authorized and made arrangements for continued picketing and paid the picketers. While this movement was under way thirty of the defendants, members of the Shoe Workers’ Protective Union who were employed by the plaintiff, without giving any notice abandoned their work and some of them joined the picketers. The judge states that the picketers and the participating employees “ acted in pursuance of a conspiracy to induce by picketing those who were about to enter the plaintiff’s employ to refrain from doing so, and to compel or induce those remaining in the plaintiff’s employ to quit the Shoe Workers’ Protective Union.” The picketing then inaugurated was continued every working day until the case was tried in January, 1923. It is found “ that the picketing annoyed the plaintiff’s employees and made them apprehensive lest they might not be able to continue at work in the plaintiff’s factory unmolested.” During the progress of the strike thirty-five of the plaintiff’s employees, joined the union of the defendants and assisted in maintaining the picketing. “ It is reasonable,” says the trial court, “ to infer that these thirty-five persons quit the plaintiff’s employ and joined the Shoe Workers’ Protective Union as a result of the strike and the picketing, and I so find. ... I find that the defendants conspired to interfere with the plaintiff’s business, and injure it, and that they did interfere with and *596injure it. I find that the defendants conspired to interfere with the employment of those continuing in the plaintiff’s employ after October 4, and that they did interfere with it. It was the contention of the defendants . . . that their purpose in instituting and maintaining the strike was to get all of the plaintiff’s work or none of it. I do not find that such was their purpose. I find that their purpose was to compel the plaintiff to give all its work to the members of the Shoe Workers’ Protective Union.” While the defendants did not solicit the plaintiff to break its contract with the Boot and Shoe Workers’ Union, they are found to have known that a contract existed and that if the strike was successful and they received all of the plaintiff’s work the contract would be broken. It is argued that the strike was lawful and the contract was void under G. L. c. 93, § 2, and the defences considered in Lovely v. Gill, are. again urged. But it was a concerted effort to force the plaintiff’s employees to leave their employment. It was successful because of picketing and intimidation. A further purpose was to compel the plaintiff to hire only members of the defendants’ union to the exclusion of all other workmen whether they were members of a rival union or were not affiliated with any association of organized labor. It has been repeatedly decided that the acts of the defendants were unjustifiable. New England Cement Gun Co. v. McGivern, 218 Mass. 198, 203. Tracey v. Osborne, 226 Mass. 25, 29. Folsom Engraving Co. v. McNeil, 235 Mass. 269, 277. United Shoe Machinery Corp. v. Fitzgerald, 237 Mass. 537, 544. It is found that when the attack began sixty-five of the defendants were members of the Boot and Shoe Workers’ Union, and the judge ruled that as to them, “ the strike was also illegal because of their violation of that contract.” But no question of specific performance is presented, and the claim for damages was not pressed at the trial. It is apparent however on the record that they left work and acted with the other defendants in their unlawful efforts to force the plaintiff to close its factory, or yield to unjustifiable demands. Folsom Engraving Co. v. McNeil, 235 Mass. 269, 276. Hotel & Railroad News Co. v. Clark, 243 Mass. *597317. The decree although properly entered on the facts found, and the issues presented by the bill, is too broad in scope. While it should be modified by inserting in the sixth line after the word “ intimidation,” the words “ as alleged in the bill and,” no further changes are necessary. Vegelahn v. Guntner, 167 Mass. 92, 99. Aberthaw Construction Co. v. Cameron, 194 Mass. 208, 215. Hotel & Railroad News Co. v. Clark, 243 Mass. 317. It follows, that in the first case the decree is affirmed with costs, and in the second case an interlocutory decree overruling the demurrer is to be entered; while in the third case the decree is to be modified in accordance with this opinion, and as thus modified it is affirmed with costs.

Ordered accordingly.