Marc Toberoff, the attorney for the heirs to the co-creators of “Superman,” is accusing DC Comics of a “desperate and cynical strategy” of targeting him as a way to stall his pursuit of copyright claims to the Man of Steel.

DC Comics, a division of Warner Bros., in May filed suit against Toberoff and his clients, charging him with poisoning DC Comics’ relationships with co-creator Jerome Siegel and Joseph Shuster’s heirs in an attempt to gain his own control over the copyrights.

Toberoff’s attorney, Richard Kendall, filed motions on Friday in U.S. District Court in Los Angeles seeking to dismiss the suit. Among other things, he cited protections from California’s “anti-SLAPP” laws, designed to curb lawsuits filed with the intention of intimidating the opposition by delay and legal expense. (SLAPP stands for “strategic lawsuit against public participation”).

DC Comics and Warner Bros. stand to lose a great degree of control over Superman in 2013, putting in doubt their ability to exploit the character onscreen and in a host of other projects.

A provision of the Copyright Act allows creators and their heirs and estates to recapture their creations under certain circumstances, regardless of whether the rights were signed away in prior agreements.

With two U.S. District Court decisions in 2008 and 2009, Toberoff successfully recaptured key portions of the “Superman” storyline for the Siegel heirs. Toberoff also represents Shuster’s nephew, Mark Warren Peary, executor of the Shuster estate, which is seeking to recapture the other half of the rights in 2013.

“The transparent purpose of DC’s lawsuit against Mr. Toberoff is to re-litigate the issues that DC has already lost, disrupt the relationship between Mr. Toberoff and his clients, and delay the final reckoning between DC and Mr. Toberoff’s clients,” Toberoff’s attorneys wrote in their motions.

DC Comics, represented by Daniel Petrocelli, in May accused Toberoff of having an ulterior motive that went beyond legal representation and claimed that he had wrested a 47.5% stake in the heirs’ claimed rights, while the Siegel heirs get 27.5% and the Shuster estate gets 25%.

The suit accuses Toberoff of preventing the Siegel and Shuster heirs “from freely entering into agreements with DC Comics — even if it was in their respective economic interest to do so.”

But in his filings, Toberoff said that, for at least the past five years, he has only been on retainer with the Siegel heirs and Shuster’s executor.

According to Toberoff, the Siegel heirs in October 2002 did enter into an agreement with IP Worldwide, a joint venture he formed with Endeavor partner Ari Emanuel for the purpose of acquiring and packaging intellectual property rights. But that agreement expired in 2005.

And in 2001, Toberoff’s “loan-out” company, Pacific Pictures Corp., entered into an agreement with Peary and Shuster’s sister, Jean Peavy, to retrieve, enforce and exploit Shuster’s creations. But those agreements were cancelled in 2004.

Toberoff also denied DC Comics’ contention that he had coaxed the Siegels out of a settlement with DC Comics in 2002, even as they had other legal representation at the time.

In his filings, Toberoff said that Emanuel had, in early August 2002, made a $15 million offer to purchase the Siegels’ rights plus a portion of the “back end.” But that offer was made to their attorney, Kevin Marks of Gang, Tyre, Ramer & Brown, and they did not get a response from the Siegels to the offer.

Toberoff also said that he did not consult the Siegels — and had yet to meet them — when they dropped Gang, Tyre, and formally called off all negotiations with DC Comics in September 2002. Only the next month, Toberoff said, did they contact him for representation.

Perhaps most intriguing about DC Comics’ suit against Toberoff was the inclusion of an unsigned document, called the “Superman-Marc Toberoff Timeline,” that spelled out a series of tactics on the part of Toberoff through which he purportedly claimed as “much ownership of the Superman copyright personally as he can.”

The DC suit says that the document was written by an attorney previously employed at Toberoff’s firm. It was delivered to Warner Bros. in 2006 along with a pile of other files that Toberoff says were privileged attorney client documents stolen from his firm.