NEW YORK — Before catching a plane to California, Guess Inc. chief executive officer Paul Marciano spent several more hours in a federal court here trying to clear his company’s name of allegations that it has been knocking off Gucci’s trademarks for decades.Guess attorney Daniel Petrocelli of O’Melveny & Myers LLP spent two hours questioning his client about the origin of his brand’s designs in response to claims made by Gucci’s legal team, which grilled Marciano Wednesday for roughly four hours.The court case, which began last week, involves allegations by Gucci that Guess and its exclusive licensee for footwear, Marc Fisher Footwear, devised a “massive scheme” to knock off Gucci product. Gucci is seeking $221 million in damages, and a permanent injunction that would keep Guess from making and selling goods that include its diamond-shaped logoed pattern, square “G” design and tri-striped motif.RELATED STORY: Guess Inc.'s Paul Marciano Testifies in Courtroom Battle >>Guess, which denies Gucci’s claims, said it takes “inspiration” from a host of brands, including Gucci, but that its designs differ.With his brother Maurice looking on, Paul Marciano painstakingly detailed the evolution of the brand’s Quattro G logo, as well as its script logo, which, according to Gucci, might “confuse” consumers as it has similar trademarks. Material to Guess’ case is either proving it developed the design first, or demonstrating that other brands have used similar designs as well.When the topic of the square “G” arose, Marciano, who was unable the previous day to prove that fashion house Givenchy used the square “G” before both Gucci and Guess, had an epiphany.“This morning, at the courthouse, we saw the square G on a handbag,” an excited Marciano said, as his lawyers displayed a photo of what appeared to be a logoed Givenchy clutch.Gucci’s lawyer looked flustered as the Guess team explained that they had snapped a photo of the purse of a woman they met that morning.“We asked permission first,” said a Guess lawyer, replying to presiding Judge Shira Scheindlin’s inquiry of the photo’s origin.“It’s a counterfeit,” said Gucci’s attorney, Louis Ederer of Arnold & Porter LLP, after inspecting the placement of the logos on the photo of the clutch.“But we asked the lady,” Marciano said. “She said it was real.”“Of course she told you that,” the judge said with a chuckle.The matter was dropped. Despite the lighter moments, the judge’s patience was running thin as lunchtime approached.Petrocelli wrapped up his examination by asking why Guess hadn’t terminated its partnership with Marc Fisher Footwear, which, in 2008, created Guess sneakers that Marciano said looked so similar to Gucci sneakers that he was “embarrassed.” Guess quickly pulled those shoes from the market.“You have to put it in perspective. Marc Fisher was a new licensee at the time,” Marciano said. “There was a learning curve…but we acted within weeks of a mistake.”Much of Marciano’s testimony centered on the history of the Guess brand, its retail locations and its iconic marketing and advertising campaigns.The case was adjourned until Monday and the trial is slated to end next week.