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“AFM lobbied for production incentives to help keep work at home in the U.S.,” Hair told The Hollywood Reporter. “We think it’s unfair for them to take the cash and then run to Europe.” He raised the possibility, perhaps rhetorically, of the union returning to Congress and advocating repeal of incentives.

A Marvel spokesperson declined to comment.

Also irksome to the AFM is a perceived double standard. “Everything else in their film production from the stars to the grips and truck drivers is unionized,” said Marc Sazer, president of an AFM affiliate, the Recording Musicians Association.

That issue’s not limited to Marvel, of course; the AFM finds itself the odd man out more often than most Hollywood unions. Tentpole films often feature wall-to-wall music, but the tunes are frequently offshored. Indeed, the union picketed Lionsgate in January, targeting a Mad Men shoot but focusing at least as much on Lionsgate’s high profile Hunger Games, which – like The Avengers – decamped to the Continent when it came time to record the score.

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That picketing helped lead to a union deal the following month – but for Mad Men only, not Lionsgate’s other projects.

Nor is the AFM the only union with tentpole issues. IATSE has been attempting to organize visual effects workers, most recently at Sony Pictures Imageworks, but so far unsuccessfully. The IA has scheduled an open meeting on Sunday to publicize its efforts.

Bookmark The Hollywood Reporter’s Labor Page for the most in-depth coverage of entertainment unions and guilds.

Email: jhandel@att.net

Twitter: @jhandel