Macgillivray said in an email interview that, while he disagreed with Zack about what was good for authors, Zack was "fierce" as opposing counsel but a "sweet person" outside of her role as an advocate.
Zack also established very strong precedent in the Second Circuit for book authors, whose books were published in the 1960s, '70s and '80s, that, when contracts are silent regarding electronic rights, those rights are retained by authors, Boni said. That case was Random House v. Rosetta Books.
Zack was a shareholder at Kohn Swift from 1988 to 2004, and was associated with Cleary Gottlieb Steen & Hamilton in New York from 1981 to 1986.
Zack also was deeply involved with Community Legal Services of Philadelphia, CLS Executive Director Cathy Carr said.
Zack served on the board from 1994 to 2001, including as treasurer; co-chaired the fundraising campaign; worked on attorney fees issues for CLS; and volunteered when she first got ill with cancer and was not working as an attorney at CLS's North Philadelphia office doing intake work of clients.
Carr said of Zack that she was "an amazing combination of someone, both kind and generous, with lots of grace and someone who was an outstanding lawyer's lawyer."
She also clerked for U.S. District Judge Charles L. Brieant of the Southern District of New York.
Zack graduated from Carleton College and attended New York University School of Law.
A celebration of Zack's life is scheduled from 6 to 9 p.m. Monday at Hilltop House, 570 Beaumont Road, Devon, Pa.