Los Angeles — Attorneys for members of rock giant Led Zeppelin and the estate of the man alleging they stole musical elements of their iconic song Stairway to Heaven made final pleas to jurors Wednesday as the high-stakes copyright trial came to an end.

In his closing arguments, Francis Malofiy, the attorney for the estate of singer Randy Wolfe, returned to simple themes he raised at the start of the weeklong trial, of fairness and giving due credit.

“We respect and we value creation,” Malofiy told the panel of four men and four women. “Creation does not mean copying. … Creation means doing something that is unique and memorable.”

But Peter Anderson, who represents Zeppelin guitarist Jimmy Page, singer Robert Plant and various music companies associated with the band, pushed back pointedly, saying Malofiy had failed at every turn to make his case. Anderson argued there had been no compelling evidence that Zeppelin members ever heard a performance of Wolfe’s song Taurus and that any similarities between the two songs were because both relied on “basic building blocks of music” that are owned by no one.

It was a final round of jabs in a contentious legal battle that revisited the creation nearly half a century ago of one of rock music’s most momentous songs. Plant and Page, larger-than-life rock figures, took the stand to defend themselves against claims they lifted a short segment of Taurus for the famous acoustic guitar opening of Stairway.

The jury deliberated for about four hours Wednesday but failed to reach a verdict. Discussions were scheduled to resume Thursday morning.

At stake are potentially millions of dollars in royalty payments, which would go to the estate of Wolfe, the guitarist for Spirit, an L.A. band that, while largely forgotten today, gained some popularity in the late 1960s and ‘70s for its novel blend of rock, jazz and other styles. Wolfe died in 1997.

The suit follows another high-profile infringement case last year in which R&B-soul singer Marvin Gaye’s family was awarded $7.4 million by a jury that decided pop stars Robin Thicke and Pharrell Williams’ monster hit Blurred Lines had infringed on Gaye’s Got to Give It Up. A judge later reduced the award to $5.3 million.

The disputed musical ground at issue in the trial comes down largely to a brief passage that arrives 45 seconds into Taurus, an instrumental from Spirit’s 1968 debut album. Those notes, which evoke centuries-old Renaissance folk music, sound similar to the opening guitar chords of Stairway, which was released in 1971, three years after Taurus.

Malofiy struggled with a difficult legal obstacle throughout the trial: U.S. District Judge R. Gary Klausner ruled the jury would not hear Taurus the way Spirit performed and recorded it. Instead, sticking to well-established copyright law, the judge ruled the only version of the song in question was the sheet music submitted to the U.S. Copyright Office.

The attorney tried several times to make the jury aware of the recording of Taurus, but was stopped by Klausner, who admonished Malofiy repeatedly for inappropriate lines of questioning, procedural missteps and other gaffes.

Malofiy made one last audacious try Wednesday in his closing argument, reminding jurors that Page and Plant had not wanted them to hear Taurus with all its parts. Klausner interjected, telling Malofiy the bid was “inappropriate.”

In summarizing his case for the jury, Malofiy reiterated his basic claims: that members of Zeppelin had ample opportunity to hear Taurus performed, the beginning of Stairway uses a musical structure that was unique to Taurus, and Wolfe’s estate deserves some of the many millions of dollars Stairway has allegedly earned.

The similarities between the two songs, he said, stemmed from a “very unique” progression of chords moving down the musical scale that Wolfe used in Taurus and that appear in Stairway as well.

In trying to underscore opportunities Zeppelin members had to hear the song, Malofiy portrayed Page and Plant as being dishonest and having “selective memories.” He zeroed in on interviews Page gave at the time praising Spirit’s music and his testimony during the trial that he owned an album with Taurus on it, but never listened to the song.

“Are those convenient facts they’re remembering? Is that selective memory? Or is that what really happened?” Malofiy asked.

Anderson followed, framing the case as a series of baseless accusations that Malofiy had promised the jury he would prove and then failed to make good.

He pointed to what he said were gaping holes in the case, including the claim that a music company, not Wolfe, owned the copyright to Taurus.

To underscore his point, Anderson noted that Malofiy failed to produce the original registration of the copyright claim for the song.

And claims that Zeppelin had watched Spirit perform at various music festivals fell far short as well, Anderson said.

“There has been no evidence showing that ‘Taurus’ was performed live at any performance where members of Led Zeppelin were in attendance,” Anderson said.

Anderson also tried to cast the trustee of Wolfe’s estate, Michael Skidmore, as an opportunist trying to make a money grab. Neither Wolfe, Wolfe’s mother, who controlled the trust before she died, or the music company that holds the copyright on the song, took legal action, he said.

Malofiy’s claim that the composition of Taurus was musically unique didn’t hold up either, Anderson said. He recapped the testimony of dueling musicology experts, saying even the professor who testified against Zeppelin had to concede the descending chord progression underlying each song was a common musical element.