1. What is a “sympathy strike?”
2. Does a general no-strike clause that does not reference sympathy strikes constitute a waiver of the right to participate in a sympathy strike?

[Teamsters Local 952 represented the employees at the Standard Concrete Products, Inc., plant in Corona, California. It also represented employees at three sites in Orange County, California, in a separate bargaining unit with a separate collective bargaining agreement. Failing to make progress in negotiating a new collective bargaining agreement, Local 952's Corona bargaining unit went on strike on January 5, 2000, and extended picket lines to the three facilities in Orange County. The Orange County bargaining unit participated in a sympathy strike and refused to cross the Corona bargaining unit's picket line. The employer sued Local 952 in the U.S. district court for damages for breach of the no-strike clause in the Orange County CBA. From a judgment for Standard Concrete for $802,237, the union appealed.]
PREGERSON, C. J.…
Section 7 of the National Labor Relations Act guarantees workers and unions the right to engage in a sympathy strike, i.e., to refuse to cross the picket line of another bargaining unit that is on strike against its employer. Oil, Chem. and Atomic Workers Int'l Union, Local 1-547 v. NLRB, 842 F.2d 1141, 1143 (hereinafter Local 1-547) (9th Cir. 1988). The right to strike and sympathy strike may be waived in a CBA.
To do so, the union must make a "clear and unmistakable" waiver in the CBA. Children's Hosp., 283 F.3d at 1192; Local 1-547, 842 F.2d at 1143. We require a specific "clear and unmistakable" waiver of a Union's right to sympathy strike because:
[I]f a Union is negotiating away employees' rights that are fundamental to the collective bargaining process, any proposed contract must unambiguously put those employees on notice of the waiver.

Children's Hosp., 283 F.3d at 1192.

In Children's Hospital we made clear that "[a] general no-strike clause that does not specify whether sympathy strikes are included or excluded does not, simply by virtue of its incorporation in a collective bargaining agreement, constitute such a clear and unmistakable waiver [of sympathy strikes]." Children's Hosp., 283 F.3d at 1192. We must "examine the relevant extrinsic evidence to determine if the parties intended that general [nostrike] language to include sympathy strikes." Id. at 1194. The burden is on the "employer to show by clear and unmistakable evidence that a general waiver of the right to strike includes sympathy strikes." Id. at 1195.…
We find that Children's Hospital is controlling. There is evidence in the express text of the Orange County CBA that the parties did not intend to bar sympathy strikes when they agreed to a general no strike clause. Article IX, Section 1 of the Orange County CBA provides: "No employee shall be discharged or discriminated against because of his/her membership in the Union or Union activities, including his/her refusal to cross a picket line approved by the Union." If Standard Concrete intended the no strike clause to encompass a ban on sympathy strikes, it would not have agreed to safeguard the jobs of Local 952 members that refuse to cross a picket line.
We conclude that Local 952 did not make a clear and unmistakable waiver of its members' right to refuse to cross the picket line of another union or bargaining unit of the same union.
Reversed.