According to a report in the Los Angeles Times, the studio mistakenly placed Streep's name in SAG's best actress competition instead of the best supporting actress category for her supporting role as author Susan Orlean in the black comedy Adaptation.
Sony discovered the error when the ballots were mailed out last month and appealed to SAG to place Streep in the proper category. The studio even offered to pay to print and mail corrected ballots, but SAG refused, fearing it would set a bad precedent, The Times reports.
The blunder may also have cost Streep a best actress nod for her leading role as a woman throwing a party for a dying friend in Paramount Pictures' drama The Hours. Paramount also submitted Streep for a best actress nomination for that film, which may have deterred SAG voters worried that she would essentially be competing against herself.
Both Paramount and Sony said Tuesday that vote-splitting was probably why Streep failed to get a best actress nomination for either films, The Times reports.
Streep, who took home a Golden Globe award for best supporting actress earlier this month for Adaptation, also received a Golden Globe nomination for best dramatic actress for The Hours. She lost to co-star Nicole Kidman.
This is not the first time a studio snafu has caused an actress a SAG nomination. In 2002 Universal Pictures wrongly submitted Jennifer Connelly in SAG's lead actress category for her supporting role in A Beautiful Mind. While SAG's best actress award went to Halle Berry for her role in Monster's Ball, Connelly won both the Golden Globe Award and the Academy Award in the correct best supporting actress categories.
But while the Golden Globes will negotiate with studios over which category nominees belong in, occasionally vetoing a studio's preference, the SAG awards allow the studios to choose.