Could the Phillie Phanatic return to New York?

This mascot will be licensed, not sold.

Designers of the Phillie Phanatic 'sculpture' have threatened to terminate their copyright transfer after 35 years, per a lawsuit filed by the Philadelphia Phillies baseball team.

Crucially, the Phanatic was not originally a "work for hire", but owned by its creators:

Initially we leased the Phanatic to the team for appearances and paid a royalty to them for the licensed products we did. The first year of licensing we did over two million dollars in sales in the Philly area. Eventually we had a number of successful programs with teams who wanted to be able to control of the characters and were able to enforce the copyrights so we sold the Phanatic and then others to the teams.

Many made light of the mascot's pending "free agency", with the Washingtonian promoting a move to D.C. But for teams in a similar situation, such disputes could mean serious payouts - at least for lawyers - and given the time periods involved, the issue might soon touch on works in furry fandom.

U.S. law (17 USC 203) means copyright transfers made from 1978 onwards may be terminated in a way analogous to that of a revokable license - although notice must be given at least two years before termination, the date of which must fall 35-40 years after the transfer agreement was made.

Such transfers started to be reclaimed from 2013 onwards. One notable case was that of Village People lead singer Victor Willis, credited for co-authoring fan favourite "YMCA", regularly heard at furry events - who won his case for termination, despite having had support in creating the work.

According to Bill Giles, his original decision not to buy the copyright for an additional $1,300 was one of the worst decisions of his life, since the transfer cost ~$250,000 when he bought the Phillies five years later. Now, forty-one years since the Phanatic's debut appearance at Veterans Stadium, perhaps he's regretting not building the mascot himself.

Wayde and Bonnie created the legendary Phillie Phanatic, a team mascot who came with a storied background and took on a life of his own.
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Since that legendary project, Wayde and Bonnie have created 16 other mascots with entertaining identities.