By Joan Biskupic, CNN

(CNN) -- A Boston-based US appeals court has rejected a challenge to Harvard's affirmative action policy brought by a group representing Asian Americans who claimed the school discriminated against them as it favored Black and Hispanic applicants.

"Harvard has an ongoing obligation to engage in constant deliberation and continued reflection regarding its admissions policies," Judge Sandra Lynch wrote for the appellate panel, finding that the school's "limited use of race" in its admissions policy to achieve diversity is consistent with Supreme Court precedent.

"Harvard has shown that its holistic consideration of race is not impermissibly extensive," Lynch wrote.

The ruling is certain to lead to a new battle over racial affirmative action at the US Supreme Court, which has long upheld such campus practices but by narrow one-vote margins. The new 6-3, conservative-liberal, makeup of the bench, could threaten an end to practices that have boosted the admissions of traditionally disadvantaged minority students and enhanced campus diversity nationwide.

Edward Blum, president of Students for Fair Admissions, which began the lawsuit in November 2014, said the decision would be appealed. Blum has long opposed racial policies that have primarily benefited Blacks and Hispanics. He lost a Supreme Court case against the University of Texas in 2016, brought by a White student Abigail Fisher.

The sweeping decision by the 1st Circuit US Court of Appeals was also a sharp rebuke to the Trump administration whose Justice Department joined the case, siding with Blum's Students for Fair Admissions group.

The Harvard case has been closely watched from the start because of the prevalence of affirmative action practices nationwide. It took on new relevance this summer as the country focused on systemic racism, ignited by the May 25 police killing of George Floyd in Minneapolis.

One of the main points of contention was Harvard's use of a "personal" score, in addition to academic and extracurricular ratings, that SFFA challengers say allowed admissions officials to enhance the prospects of Black and Hispanic applicants and disadvantage Asian Americans.

The appeals court on Thursday rejected the claim, as had US District Court Judge Allison Burroughs after a three-week trial.

The SFFA challengers had argued that the flexible "personal" rating has led to the racial stereotyping of Asian Americans. During the trial, SFFA contended Asian Americans were typecast as one-dimensional or merely "book smart."

But the appeals court endorsed the trial judge's findings rejecting stereotyping and concluding that the personal ratings were not influenced by race.

Favorably commenting on the Ivy League school's practices, Lynch wrote that, "Harvard's interest in diversity is not an interest in simple ethnic diversity, in which a specified percentage of the student body is in effect guaranteed to be members of selected ethnic groups, but a far broader array of qualifications and characteristics of which racial or ethnic origin is but a single though important element."

Lynch's opinion was signed by Chief Judge Jeffrey Howard. Judge Juan Torruella had also heard arguments in the case last September; he died in late October.

To SFFA's contention that Harvard imposes "a racial penalty" on Asian Americans, Harvard lawyers argued that Asian Americans actually fare well under its system.

For its new class of 2024, Harvard said, Asian Americans make up 24.6% of the class; African Americans 13.9%; Latinx 11.8%; and Native Americans and Native Hawaiians, 2.0%. The remaining category, 47.7%, is overwhelmingly White students.

Harvard lawyers also have noted throughout the litigation that when the Supreme Court in 1978 first upheld affirmative action, the justices favorably cited the Harvard model.

In the 1978 decision, Regents of the University of California v. Bakke, the high court allowed colleges and universities to consider race as a "plus" factor among many criteria in admissions but forbade quotas.

Thursday's appeals court decision moves the battle over racial admissions closer to a showdown at the Supreme Court, which first endorsed racial affirmative action designed for campus diversity in 1978 by a 5-4 vote. In addition to the 2016 University of Texas dispute, the high court upheld admissions programs that consider a student's race, in case from Michigan in 2003.

That milestone 2003, along with the Bakke decision, remain the law. That could change with the new six-justice conservative dominance. If the court were to take up the appeal from the Harvard challengers, the case would not likely be heard until later in 2021.