The documentary “O.J.: Made in America” swept most of the top doc awards this past awards season, including the Academy Award for Best Documentary Feature. But the eight-hour, five-part series will likely be the only such film ever to win an Oscar, because on Friday the Academy announced new rules that make multi-part series ineligible.

Other changes include opening up nominations voting for the Best Animated Feature category, and expanding the number of potential nominees in the Best Picture and Best Original Score categories.

The documentary change was probably the most significant move. “O.J.” originally screened as a seven-hour-and-47-minute feature film at the Sundance Film Festival, and it had theatrical qualifying runs in New York and Los Angeles. But the Ezra Edelman work was commissioned by ESPN for its “30 for 30” series, where it ran as a five-part miniseries.

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In the nonfiction film arena, the lines are often blurry between film and television. But “O.J.” drew criticism for being a TV-bred project even as it was winning film awards, and many in the Academy were worried that its victory would open the floodgates for other made-for-television miniseries to qualify as films unless the Oscar rules were changed.

Although the rule declares that “multi-part or limited series” are ineligible, the Documentary Branch Executive Committee will have the authority to make determinations as to eligibility.

In the animation category, the new rule opens up nomination voting to the entire membership of the Academy. In the past, nominations have been voted by invited committees made up of a mixture of members of the Short Films and Feature Animation Branch and members from other branches. The committees have been under increasing criticism in recent years for shunning films like “The Lego Movie” and showing a marked preference for hand-drawn or stop-motion films over CG movies.

Beginning this year, all members of the Academy will be invited to vote in the nominating round and will not have to attend special screenings. The move should substantially increase the number of voters in the category, and perhaps lessen the bias toward old-school animation.

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In the Best Picture category, a new rule reinforces that a team of two people can be considered a single producer, making it possible for more producers to receive nominations. And the Music Branch will now allow a film score written by three or more “equally contributing” composers. In the past, it was extremely difficult for a score written by two composers to qualify, and impossible for a score written by more than two to become eligible.

The changes were recommended by individual branches and approved by the Academy’s Board of Governors at a meeting last week.

From the press release announcing the changes:

“For the first time, nominations voting in the Animated Feature Film category will be opened up to the entire eligible voting membership. Invitations to join the nominating committee will be sent to all active Academy members, rather than a select craft-based group. Voting in the nominations round will now be preferential instead of based on a numerical scoring system. Members participating on the nominating committee may view films in their theatrical runs or at other screenings, through the Academy’s streaming site or on DVDs/screeners to qualify to vote.

“In the Documentary categories, multi-part or limited series are not eligible for awards consideration. The Documentary Branch Executive Committee will resolve all questions of eligibility and rules.

“In the Best Picture category, in determining the number of producers eligible for nomination, a bona fide team of not more than two people shall be considered to be a single “producer” if the two individuals have had an established producing partnership as determined by the Producers Guild of America (PGA) Producing Partnership Panel. Final determination of the qualifying producer nominees for each nominated picture will be made by the Academy’s Producers Branch Executive Committee.

“In the Music (Original Score) category, in the case of a score that has three or more equally contributing composers, the composers may be considered as a group. If the score wins the Original Score award, the group would receive a single statuette.”

Other rule changes fall under the category of what the Academy calls “housekeeping adjustments.”