Supreme Court Justice Elena Kagan Geeks Out on Spider-Man

PHOTO: A Spiderman balloon floats at the 88th Annual Macys Thanksgiving Day Parade on Nov. 27, 2014 in New York City. Brad Barket/Getty Images
A Spiderman balloon floats at the 88th Annual Macy's Thanksgiving Day Parade on Nov. 27, 2014 in New York City.

Elena Kagan’s spidey senses are tingling.

The Supreme Court justice penned an opinion released today that ruled against a toymaker attempting to collect royalties on the Web blaster, a gadget that shoots silly string from a glove, Spider-Man style.

In the 6-3 decision, the court ruled that Marvel Entertainment -- which purchased the toy's patent in 2001 for $516,000 plus 3 percent of net sales -- can continue to sell the contraption without paying additional royalties to the inventor, Stephen Kimble, because the patent is expired.

Justice Kagan, 55 -- “an avid fan of comic-book-based action films,” according to the "Supreme Court Review" -- had a little fun with the references to Spider-Man's alter ego, Peter Parker.

Spider-Man, Spider-Man

“The parties sent no end date for royalties,” Kagan wrote, “apparently contemplating that they would continue for as long as kids want to imitate Spider-Man (by doing whatever a spider can).”

Kagan’s parenthetical is a throwback to the 1967 TV theme song: "Spider-Man, Spider-Man / Does whatever a spider can."

Was Kagan humming in her chambers? We’d like to think so.

With Great Power ...

In another parenthetical citation, Kagan quotes Peter Parker’s Uncle Ben: “[I]n this world, with great power there must also come -- great responsibility.”

For Spider-Man, that may mean vanquishing a supervillain.

For the court, that means declining to overrule a long-standing precedent that patent holders aren’t entitled to royalties after the patent expires.

A ‘Web of Precedents’

This one’s a bit more subtle.

“The decision’s close relation to a whole web of precedents means that reversing it could threaten others,” Kagan writes.

... Web -- get it?

Superpower Patents

“Patents endow their holders with certain superpowers, but only for a limited time,” Kagan wrote.

And once the "superpower" expires, Marvel Entertainment can stop paying royalties.

Marvel Entertainment is a division of The Walt Disney Company, which also owns ABC News.

ABC News' Jill Ornitz contributed to this report.