It took two years of court wrangling, but DC Comics ultimately found the legal kryptonite to shut down an attempt by the heirs of a Superman co-creator to recapture rights to the heroic character. Because of an agreement they signed in 1992, the family of artist Joe Shuster won't be able to claim the "Man of Steel" as their own.

The Superman battle is one of the most closely watched battles over copyright "termination," a process through which artists can take back the rights to their old works. Such termination notices are allowed by Congress as part of the 1976 Copyright Act, and Shuster's heirs hoped the law would allow them to take back the character that he and writer Jerry Siegel created in 1938.

Siegel, Shuster, and their heirs still made plenty of money off the comic book hero from Krypton—about $4 million since 1975, according to the judge's order [PDF] released yesterday.

Copyright termination essentially allows artists, musicians, and other creators to "undo" any deal they agreed to that transfers their copyrights to another person or company... as long as they wait 35 years first. The idea is that struggling artists who create a blockbuster work may have signed away rights at a time when they didn't have the leverage to negotiate a good deal. Through the termination clause, Congress gave such artists, or their heirs, the right to re-capture ownership of their most popular works.

The termination battles are heating up now, because 2013 is the year when the first 'round' of works from 1978 are up for grabs.

The victory for DC comics clears the company from legal burdens when it launches a new Superman movie, Man of Steel, onto the big screen next year.

The judge's reasoning in this case: copyright termination can only apply to pre-1978 deals. But after co-creator Joe Shuster passed away in 1992, his brother Frank and sister Jean Peavy signed a deal with DC Comics that would cover Shuster's debts and pay Jean Peavy $25,000 a year for life (Shuster had no wife or kids, so his siblings are his legal heirs.)

That 1992 deal ultimately earned Peavy more than $600,000, and DC Comics' lawyers argued it supersedes any earlier deal. The judge ultimately agreed: because of its late date, it can't be overturned using the copyright termination rules.

How much should an artist earn for creating an icon?

The creators of the famous comic hero were hardly impoverished. As the order details, even back in the 1940s Shuster and Siegel stood to make about $2 million. The co-creators filed their first lawsuit against DC Comics in 1947, but settled the following year, acknowledging that DC owned "all rights in Superman."

In 1975, they signed an agreement with DC that provided "lump sums of $75,000 each, lifetime annual payments of $80,000 each per year, survivor payments to their heirs, and insurance coverage, as well as 'credits' on new Superman works," according to the order. All told, the Siegels and Shusters were paid about $4 million under the 1975 agreement, not including medical benefits, according to the judge's calculations (which adjusts all the figures for inflation, converting them to today's dollars).

After Shuster died in 1992, his sister Jean Peavy struck a deal with DC to get $25,000 per year. She also asked DC for additional money each year, noting that she wasn't going to try to reclaim the copyright in court like Siegel's heirs had done: "I want you to know that I intend to continue to honor our pension agreement," wrote Peavy. "I would, however, appreciate a generous bonus for this year as you had done many times in the past."

Between 1993 and 2001, DC paid Peavy bonuses between $10,000 and $25,000 on eight different occasions, all the while making its position clear that it had no legal obligation to do so. In 2003, Peavy's son Mark Warren Peary (born Peavy) moved to terminate the copyright anyhow.

In court papers (PDF), DC Comics lawyers say their client took care of Jean Peavy and continue to pay her every year as promised. However, in 2003, her son Mark Warren Peary worked with a lawyer and "intervened to disrupt the family’s longtime contract with DC," wrote lawyers representing DC Comics.

To bolster their case, the Shusters pointed to a 2008 decision in which the daughter of the writer of the novel Lassie Come Home was able to terminate a copyright grant. The judge found there was "no ambiguity" in the 1992 agreement and noted that unlike the Lassie Come Home situation, the Superman heirs were aware of the copyright termination rights and were in fact able to obtain hundreds of thousands of dollars in benefits from their deal.

The Shusters' attorney, Marc Toberoff, declined to comment today on the order. In court papers, he argued the Shusters were a textbook case of what Congress intended when it allowed for copyright termination. He said the purpose of the process was to "enhance the authors' position," and give creators some leverage that would prevent "exploitation" by publishers.

The original 1938 agreement signed by Siegel and Shuster, without the aid of a lawyer, "would later be held to have granted Superman to DC for $130," wrote Toberoff. It wasn't until 1975—under pressure from a national cartoonists' group—that Warner Bros. (parent company of DC Comics) agreed to pay Siegel and Shuster "a modest pension." The company was worried about negative publicity, he wrote.

The party attempting to recapture the copyright in this case is Pacific Pictures Corporation, a joint venture owned by Toberoff and the Shuster heirs. Toberoff also represents the heirs of some other well-known artists engaged in battles over copyright terminations. His clients include the children of Jack Kirby, who created some of Marvel Comics' most famous characters; and the children of Ray Charles, who are seeking to reclaim copyright on 51 of the artist's songs.