At issue is whether changing the U.S. system from a "first-to-invent" system to a "first-inventor-to-file" system violates Article 1, Section 8, Clause 8 of the Constitution. That clause grants Congress the power to "promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries."

Supporters of the bill, called the America Invents Act, argue that moving to a "first-inventor-to-file" system is in line with the Constitution and also has the benefit of moving the U.S. closer to the "first-to-file" system that most of the rest of the world uses.

"The bill's inclusion of a move to a first-inventor-to-file system is absolutely consistent with the Constitution's requirement that patents be awarded to the inventor," House Judiciary Committee Chairman Lamar Smith (R-Texas) argued.

But several Republicans and Democrats objected, arguing that the proposed change would put in place a new requirement that inventors file for their patents first in order to be awarded rights that they should already have under the Constitution by having invented a novel product or process.

"Supporters of this bill say it's an attempt to modernize our patent system," Rep. Marcy Kaptur (D-Ohio) said. "What they really mean is that this bill Europeanizes our patent system by granting the rights to an invention to whoever wins the race to the patent office."

She was joined by Rep. Jim SensenbrennerFrank (Jim) James SensenbrennerHouse fails to override Trump veto on border wall The 25 Republicans who defied Trump on emergency declaration Hillicon Valley: US threatens to hold intel from Germany over Huawei | GOP senator targets FTC over privacy | Bipartisan bill would beef up 'internet of things' security | Privacy groups seize on suspended NSA program | Tesla makes U-turn MORE (R-Wis.), a senior member of the Judiciary Committee.

"Unlike what my friend from Texas Mr. Smith has said, this bill is unconstitutional, and voting for this bill will violate one's oath of office," he said. "A first to invent and first to file provision is unconstitutional because it adds a layer of compliance in winning a race to the patent office for someone who already has that right."

Kaptur and Sensenbrenner were joined in opposition to the bill by Republican Reps. Lee Terry (Neb.), Dana Rohrabacher (Calif.), and Scott GarrettErnest (Scott) Scott GarrettManufacturers support Reed to helm Ex-Im Bank Trump taps nominee to lead Export-Import Bank Who has the edge for 2018: Republicans or Democrats? MORE (NJ). Garrett argued that the bill is unconstitutional because it gives the right to award the patent to a government agency, and ignores language in the Constitution saying Congress must help secure rights to authors and inventors.

But Smith was joined in support of the bill by members of both parties. Rep. Jerrold Nadler (D-NY) said the bill still requires patent seekers to be inventors, and argued that the Constitution is not explicit on how Congress must ensure patent rights. Rep. Bob GoodlatteRobert (Bob) William GoodlatteTop Republican releases full transcript of Bruce Ohr interview It’s time for Congress to pass an anti-cruelty statute DOJ opinion will help protect kids from dangers of online gambling MORE (R-Va.) agreed.

"This is first inventor to file," Goodlatte said. "You must be a bona fide inventor to qualify for this." Both Nadler and Goodlatte are on the Judiciary Committee.

After debate on the constitutionality of the bill, members began general debate on it shortly before 8 p.m., and was expected to begin considering amendments to the bill Wednesday night.