> However, the artists would paint over previous works, so it's not like they were permanent installations, they lasted from days to on occasion a year.

That's not true. Some of the works were permanent installations, including tribute and memorial works from artists who have died. Only some spaces were designated for temporary installation.

> There was impermanence about the art. So, i think it's mostly about not wanting to lose their "canvass" than to preserve the art.

There's no need to put "canvas" in scare quotes. There's plenty of case law that helps define what an installation is, in the context of art. This isn't a novel concept.

> Given that the canvass was a building owned by someone else, I don't see much of a case.

The owner agreed to let them use the space (and even charged them for it, along with double-dipping into tax write-offs for the building). Legally, that gives them a pretty strong claim to the space.

Still, its a traditionally impermanent art form - so the injury to the artists is not the same as, for instance, destroying a statue or slashing a painting.

On a tangent, statues can be moved, murals can be moved, castles can be moved, bridges can be moved, etc. I can see, if someone wanted to buy up the structure and move it to some alternate location, that could have been an option, however, I'm not sure that was pursued as an option.

> Still, its a traditionally impermanent art form

The entire point of 5Pointz and their argument is that it's not an inherently impermanent art form, any more than other installation art (which is already established legally not to be impermanent).

yet, graffiti is always an installation art form, and the vast majority is inevitably destroyed over time. So I argue its traditionally impermanent.

The graffiti community is very diverse and organic, lacking formal definitions or standards- ha! Also, things from the inside can/are perceived differently than from the outside. I have friends that make a distinction, broadly, between graffiti writers and graffiti artists. The ones I call orthodox think it’s only graffiti if you do it on a train, everything else is “street art”- and that being a derogatory term. Train, as a medium, is accepted to be pretty ephemeral. Then you have the bomber mindset, which focuses on difficulty of placement and quantity, also understood to be ephemeral. Then there’s walls and graffiti artists, which do legal walls more often and do expect more permanent installations... the only spot where I’ve seen different kind of writers converge were Walls of Fame, which always felt more organized and with more explicit rules around them and more permanent. 5pointz was both a legal wall and a sorts of Wall of Fame, known to the graffiti community- at large- around the world.

Regarding 5pointz, the only part that I find interesting is the debate around the owner benefiting from tax breaks.

As I understand the situation; the owner was claiming the building was art to get tax cuts, then decided to sell and argued the building was not art. I feel graffiti is irrelevant here.

Agreed. Even in the heyday of the 70s and 80s, people sprayed over each others paint, be they the owners or other rival taggers. So, historically, it has been impermanent.

Historically, the contested real estate would be taken back if the crossing writer was a toy who lacked respect for the art and understanding for the intention for the piece to stay up. It shouldn't be hard to find ten year old pieces, in New York surely older.